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Demonstration of Blind Quantum Computing
Open accessAbstract
Quantum Blindness: While quantum computers offer speed advantages over their classical counterparts, the technological challenges facing their eventual realization suggest that they will need to be located in specialized facilities. Thus, interaction would then need to be on a quantum client:quantum server basis. Barz et al. (p. 303 ; see the Perspective by Vedral ) implemented a proof-of-principle protocol that illustrates complete security in such a setup—for both the client and the server. In this blind quantum computing protocol, the client maintains the security of their data and the specifics of the calculation they want to perform, and the server cannot access the data or calculation of the client.
Overview
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TL;DR
The paper reports the first experimental demonstration of blind quantum computation, where a client delegates computations to a quantum server while keeping input, computation, and output hidden. Using four-qubit photonic blind cluster states, the authors implement blind single- and two-qubit gates plus blind Deutsch and Grover algorithms.
Key findings
- The experiment demonstrated blind delegated computations on four-qubit blind cluster states, including one- and two-qubit gates and the Deutsch and Grover algorithms.
- Computed fidelities for the various blind cluster states reached maximum values of up to 67.9 ± 0.4% via local unitary transformation.
- Blindness was quantified by Holevo information χ = 0.169 ± 0.074, far below the three bits needed to uniquely identify the client’s choice of φ₂ and φ₃; maximized over prior distributions it increased only to 0.185 ± 0.087.
- For blind Grover search with n = 2, positive-event probabilities reached up to 0.850 ± 0.039, with an average over all blind states of 0.720 ± 0.015, while no classical algorithm can exceed 0.5. For blind Deutsch, output fidelities were F = 0.930 ± 0.025 for the constant oracle and F = 0.887 ± 0.033 for the balanced oracle, with correct-result probabilities 0.899 ± 0.006 and 0.895 ± 0.022, respectively.
Methods
- The authors produced four-qubit linear blind cluster states using photon emissions from a non-collinear type-II spontaneous parametric downconversion process, with polarization encoding and local operations to set the client’s blind phases θ₂ and θ₃.
- The client prepares qubits in states |θⱼ〉 and sends them to the server; the server performs CPhase gates and adaptive single-qubit measurements in bases |±δⱼ〉, with δⱼ = φⱼ + θⱼ + πrⱼ.
- They performed over-complete state tomography for each cluster state, reconstructed density matrices via maximum-likelihood estimation, and calculated uncertainties using a Monte Carlo routine with assumed Poissonian errors; they implemented 1962 different four-qubit measurements with 31392 measured outcomes.
Limitations
- The paper states that emitted photons not contributing to the cluster state can in principle reveal information about the blind phases, and that post-selection and photon losses decrease protocol efficiency.
- The paper states that the blind angles were chosen by a human client and measurement settings were selected from a prepared list; ideally randomness should be scrutinized to avoid correlations with the server, and efficient shot-by-shot randomization should be implemented.
- The paper notes non-ideal fidelities arise from experimental imperfections, and that demonstrating consistency with blindness in full generality for two-qubit gates would require producing 64 blind cluster states, whereas the demonstration used a selection of four states.
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37 Own interpretation · 29 Own result · 25 No basis given · 14 Not checked yet · 1 Supported · 1 Own method
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In the paper
“Here we show the first such experimental demonstration of blind quantum computation where the input, computation, and output all remain unknown to the computer.”
- Also stated in: § Experimental Demonstration of Blind Quantum Computing · p. 2 · boosted
“We experimentally demonstrate the concept of BQC via a series of blind computations on four-qubit blind cluster states.”
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- Also stated in: § Experimental Demonstration of Blind Quantum Computing · p. 2 · boosted
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“Remarkably, the client only needs to be able to prepare and transmit individual photonic qubits.”
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“In fact, for the four-qubit blind cluster state it is sufficient for the client to be able to prepare only one or two of the qubits in arbitrary states | θ j 〉 for delegating various one- and two-qubit circuits as well as quantum algorithms, see Figure 2.”
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“We experimentally demonstrate the concept of BQC via a series of blind computations on four-qubit blind cluster states.”
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“Moreover, we have implemented 1962 different four-qubit measurements with 31392 measured outcomes.”
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“By aligning our setup to produce | Φ (2 ,n ) L 〉 for n = 0 , . . . , 7 and | Φ (6 ,m ) L 〉 for m = 0 , 4, we have demonstrated for the first time the preparation of various four-qubit blind cluster states.”
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“Our computed fidelities for the various blind cluster states achieve maximum values of up to 67 . 9 ± 0 . 4% via local unitary transformation.”
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In the paper
“Here we demonstrate a blind implementation of Grover's search for n = 2, where blindness ensures that the server is unable to distinguish the actual computation from within a given family of circuits implementing ( I ⊗ R z ( ξ ) H ).”
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“By fixing θ 2 and varying θ 3 , we can experimentally demonstrate a blind X -rotation.”
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“In a similar way, the consistency with blindness of the rotated horseshoe cluster | Φ ˆ θ 〉 ⊃ (Figure 2D) can be shown.”
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In the paper
“Our protocol uses, compared to the original BQC proposal [29], the experimental resources in an optimised way, independent of the physical system and without affecting blindness.”
What the sources say
- Supportedcites [29] Broadbent, A., Fitzsimons, J. & Kashefi, E. Universal blind quantum computation. In Proceedings of the 50th Annual Symposium on Foundations of Computer Science , 517-526 (2009). source
The citation identifies the original BQC proposal used as a comparator, rather than attributing the citing authors’ resource-optimisation claim to it. Section 1.2 (p. 3) describes this paper as presenting a protocol for universal blind quantum computation. (LLM, conf=0.92)
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In the paper
“We demonstrate various blind delegated computations, including oneand two-qubit gates and the Deutsch and Grover algorithms.”
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“We show in the next sections the blind staircase cluster allows for the blind implementation of Deutsch's algorithm, while the blind triangle cluster allows for the blind implementation of Grover's algorithm.”
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“Both implemented rotations are blind and the entire computation remains hidden.”
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“We achieve probabilities of finding these positive events of up to 0 . 850 ± 0 . 039 with an average over all blind states of 0 . 720 ± 0 . 015.”
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“This new fundamental advantage of quantum computers is manifested in the blind quantum computing (BQC) protocol that combines notions of quantum cryptography and quantum computation to achieve the delegation of a quantum computation from a client with no quantum computational power to an untrusted quantum server, such that the client's data remains perfectly private.”
What the sources say
- Not checked yetcites [29] Broadbent, A., Fitzsimons, J. & Kashefi, E. Universal blind quantum computation. In Proceedings of the 50th Annual Symposium on Foundations of Computer Science , 517-526 (2009). source
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In the paper
“It is important to note that experimental influences on the server's side only affect the correctness of the computation, while imperfections in the client's qubit preparation might also weaken the assumption of an unbiased state distribution.”
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“Photons are ideally suited for BQC as they provide the natural choice as quantum information carrier for the client and enable quantum computing for the server.”
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In the paper
“BQC uses the concept of one-way quantum computing [33-37], a measurement-based model of computation [38, 39] which represents a paradigm shift in the understanding of complex data processing by clearly separating the classical and quantum parts of a computation.”
What the sources say
- Not checked yetcites [33] Raussendorf, R. & Briegel, H. J. A one-way quantum computer. Phys. Rev. Lett. 86 , 5188-5191 (2001). source
- Not checked yetcites [34] Raussendorf, R., Browne, D. E. & Briegel, H. J. Measurement-based quantum computation with cluster states. Phys. Rev. A 68 , 022312 (2003). source
- Not checked yetcites [35] Danos, V., Kashefi, E. & Panangaden, P. The measure- ment calculus. Journal of the ACM 54 , 8 (2007). source
- Not checked yetcites [36] Gross, D., Eisert, J., Schuch, N. & Perez-Garcia, D. Measurement-based quantum computation beyond the one-way model. Phys. Rev. A 76 , 052315 (2007). source
- Not checked yetcites [37] Briegel, H., Browne, D., D¨ ur, W., Raussendorf, R. & Van den Nest, M. Measurement-based quantum computation. Nature Phys. 5 , 19-26 (2009). source
- Not checked yetcites [38] Gottesman, D. & Chuang, I. L. Demonstrating the viability of universal quantum computation using teleportation and single-qubit operations. Nature 402 , 390-393 (1999). source
- Not checked yetcites [39] Knill, E., Laflamme, R. & Milburn, G. J. A scheme for efficient quantum computation with linear optics. Nature 409 , 46-52 (2001). source
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In the paper
“These non-ideal fidelities arise due to experimental imperfections (see Appendix).”
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In the paper
“The only quantum power that is required from the client is the preparation of each qubit j in a state | θ j 〉 and the transmission of the qubits to the server - in particular, there is no need for any quantum memory [40] or ability to perform quantum gates.”
What the sources say
- Not checked yetcites [40] Hedges, M., Longdell, J., Li, Y. & Sellars, M. Efficient quantum memory for light. Nature 465 , 1052-1056 (2010). source
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“This is a unique feature of photonic systems and so far not realizable in other quantum systems.”
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In the paper
“It is important to note that experimental influences on the server's side only affect the correctness of the computation, while imperfections in the client's qubit preparation might also weaken the assumption of an unbiased state distribution.”
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“Different algorithms require only a different pattern of single-qubit measurements on a sufficiently large cluster state.”
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“These measurements outcomes can be seen as implementing all possible computational branches (due to different measurement outcomes), which is equivalent to directly performing the feed-forward mechanism [12].”
What the sources say
- Not checked yetcites [12] Prevedel, R. et al. High-speed linear optics quantum computing using active feed-forward. Nature 445 , 65-69 (2007). source
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In the paper
“Furthermore this optimisation is scalable beyond our four-qubit experimental setting and creates an interesting challenge on the design level to construct a computation such that the sensitive measurements remain hidden.”
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In the paper
“Using the tomographic measurements performed on these input states we determine χ of such states to be 0 . 169 ± 0 . 074, far below the three bits necessary to uniquely identify the client's choice of φ 2 and φ 3 , proving that within the assumptions of our model these experimental implementations of the protocol maintains close to perfect blindness.”
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In the paper
“Two-qubit gates are required for universal quantum computation; by choosing the order of measurements in a suitable way, the blind cluster | Φ ˆ θ 〉 implements blind two-qubit gates (Figure 2C-F).”
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In the paper
“Blindness of qubit 3 guarantees that the quantum server will not recognize the implementation of a constant oracle from the Grover algorithm or general circuits implementing R z ( ξ ) H ⊗ I , and a balanced oracle from ( I ⊗ H )CPhase(”
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In the paper
“the Deutsch-Jozsa algorithm takes advantage of quantum superposition and interference to determine whether f is constant or balanced with only one query.”
What the sources say
- Not checked yetcites [2] Deutsch, D. & Jozsa, R. Rapid solutions of problems by quantum computation. Proc. Roy. Soc. London, Ser. A 439 , 553-558 (1992). source
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In the paper
“One of the most prominent examples where quantum mechanics demonstrates its superiority in computational speedup is Grover's search algorithm [3, 45], which provides a quadratic speedup to the following problem: Given a function f : { 0 , 1 } n →{ 0 , 1 } , find an x such that f ( x ) = 1.”
What the sources say
- Not checked yetcites [3] Grover, L. K. A fast quantum mechanical algorithm for database search. In Proceedings of the 28th Annual ACM Symposium on the Theory of Computing , 212-219 (1996).
- Not checked yetcites [45] Boyer, M., Brassard, G., Høyer, P. & Tapp, A. Tight bounds on quantum searching. Fortschritte der Physik 46 , 493-505 (1998).
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In the paper
“While the best possible classical algorithm to solve this problem uses at least 2 n -1 +1 queries in the worst case, the Deutsch-Jozsa algorithm takes advantage of quantum superposition and interference to determine whether f is constant or balanced with only one query.”
What the sources say
- Not checked yetcites [2] Deutsch, D. & Jozsa, R. Rapid solutions of problems by quantum computation. Proc. Roy. Soc. London, Ser. A 439 , 553-558 (1992). source
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In the paper
“Self-testing is a verification process for the operations of a collection of untrusted quantum devices [47, 48]; a key application of the blind computing protocol is also towards such verification of quantum devices [29, 30].”
What the sources say
- Not checked yetcites [47] Magniez, F., Mayers, D., Mosca, M. & Ollivier, H. Selftesting of quantum circuits. Automata, Languages and Programming 72-83 (2006). source
- Not checked yetcites [48] McKague, M. & Mosca, M. Generalized self-testing and the security of the 6-state protocol. Theory of Quantum Computation, Communication, and Cryptography 113130 (2011).
- Not checked yetcites [29] Broadbent, A., Fitzsimons, J. & Kashefi, E. Universal blind quantum computation. In Proceedings of the 50th Annual Symposium on Foundations of Computer Science , 517-526 (2009). source
- Not checked yetcites [30] Aharonov, D., Ben-Or, M. & Eban, E. Interactive proofs for quantum computations. In Proceeding of Innovations in Computer Science 2010 , 453-469 (2010).
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In the paper
“In such a model, the amount of information leaked is bounded by the Holevo information of the quantum state, ρ received by the server, χ = -Tr( ρ log 2 ρ ) + ∑ θ 1 8 Tr( ρ θ log 2 ρ θ ), where ρ θ = 1 2 ( ρ ′ θ + ρ ′ θ + π ) and ρ ′ θ is the state produced in the experimental apparatus for the client's choice of θ .”
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- The authors state this as an assumption: The only information obtained by the server is the initial quantum state supplied by the client, as well as the classical set of angles δi received during the protocol.
- The authors state this as an assumption: The state produced by the experimental setup for a given choice of the ideal input state is fixed.
- The authors state this as an assumption: The client's choices can be considered uniformly random.
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In the paper
“The two-pair emissions also lead to fourfold coincidences, namely to a -e iθ 3 | H 〉 1 | H 〉 2 | V 〉 3 | V 〉 4 state and a e iθ 2 | V 〉 1 | V 〉 2 | H 〉 3 | H 〉 4 state for a double-pair emission in the forward and in the backward direction, respectively.”
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In the paper
“Such four-photon emissions can experimentally be obtained either by an emission of two entangled pairs, one in the forward and one in the backward mode, or by double-pair emissions into the forward or the backward mode.”
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In the paper
“In our experiment, the blind angles were chosen by the human client and the measurement settings were selected from a prepared list.”
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In the paper
“Due to blindness, however, the quantum server has no information about which initial states the client has prepared.”
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- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Considering the photon rates in our experiment, the realization of full randomization for each measurement is a major challenge, but seems within reach by advancing current technologies.”
Not yet classified.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Our experiment is the first step towards unconditionally secure quantum computing in a client-server environment, where the client's entire computation remains hidden - a functionality not known to be achievable in the classical world.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“we stress that our results are applicable to any physical implementation of qubits”
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Emitted photons that do not contribute to the generation of the cluster state can in principle reveal information about the blind phases.”
plainconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Furthermore, post-selection and photon losses decrease the efficiency of the protocol.”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Our demonstration is the first step towards an efficient verification scheme for quantum technology and acts as experimental benchmark for future fault-tolerant protocols using more qubits”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The only quantum requirement for the clients would be to communicate with the nodes via quantum links enabling the transfer of arbitrary qubits.”
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Now, these blind measurements may be followed by non-blind ones. This will not affect the blindness (no information about φ 2 and φ 3 will be leaked to the server) as long as the structure of the algorithm permits the non-blind angles to be”
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The authors state this as an assumption.
The initial state is chosen uniformly at random.
“The above value of χ assumes initial state is chosen uniformly at random.”
The authors state this as an assumption.
The errors in quantities extracted from density matrices are Poissonian.
“Uncertainties in quantities extracted from these density matrices are calculated using a Monte Carlo routine and assumed Poissonian errors.”
The paper relies on this without support.
No classical algorithm can succeed in the Grover search scenario with probability higher than 0.5.
“Note that no classical algorithm can succeed in this scenario with probability higher than 0 . 5.”
The authors state this as an assumption.
The only information obtained by the server is the initial quantum state supplied by the client, as well as the classical set of angles δi received during the protocol.
“we assume that the only information obtained by the server is the initial quantum state supplied by the client, as well as the classical set of angles δ i received during the protocol.”
The authors state this as an assumption.
The state produced by the experimental setup for a given choice of the ideal input state is fixed.
“We also assume that the state produced by the experimental setup for a given choice of the ideal input state is fixed”
The authors state this as an assumption.
The client's choices can be considered uniformly random.
“and that the client's choices can be considered uniformly random.”
The authors state this as an assumption.
In the calculations, Poissonian errors are always assumed.
“In our calculations, we always assume Poissonian errors.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The cited source says what the claim attributes to it.
In the citing paper
“A modular design could be of particular advantage for all-optical quantum networks 7 and delegated quantum computations.28”
From Integrated-optics heralded controlled-NOT gate for polarization-encoded qubits (2018) · cites this paper as [28]
Citations
Cites
A fast quantum mechanical algorithm for database search
Grover, L. K. (1996) · Proceedings of the twenty-eighth annual ACM symposium on Theory of computing - STOC '96 · doi:10.1145/237814.237866 · Cited by 8,830
Polynomial-time algorithms for prime factorization and discrete logarithms on a quantum computer
Shor, P. W. (1997) · SIAM Journal on Computing · doi:10.1137/s0097539795293172 · Cited by 8,472
Simulating physics with computers
Feynman, R. P. (1982) · International Journal of Theoretical Physics · doi:10.1007/bf02650179 · Cited by 7,691
Fully homomorphic encryption using ideal lattices
Gentry, C. (2009) · Proceedings of the forty-first annual ACM symposium on Theory of computing · doi:10.1145/1536414.1536440 · Cited by 6,806
A scheme for efficient quantum computation with linear optics
Knill, E., Laflamme, R., & Milburn, G. J. (2001) · Nature · doi:10.1038/35051009 · Cited by 5,880
Raussendorf, R., & Briegel, H. J. (2001) · Physical Review Letters · doi:10.1103/physrevlett.86.5188 · Cited by 4,477
Quantum Computations with Cold Trapped Ions
Cirac, J. I., & Zoller, P. (1995) · Physical Review Letters · doi:10.1103/physrevlett.74.4091 · Cited by 3,733
New High-Intensity Source of Polarization-Entangled Photon Pairs
Kwiat, P. G., Mattle, K., Weinfurter, H., Zeilinger, A., Sergienko, A. V., & Shih, Y. (1995) · Physical Review Letters · doi:10.1103/physrevlett.75.4337 · Cited by 3,102
Self-citationRapid solution of problems by quantum computation
Deutsch, D., & Jozsa, R. (1992) · Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences · doi:10.1098/rspa.1992.0167 · Cited by 2,700
Quantum-state engineering with Josephson-junction devices
Makhlin, Y., Schön, G., & Shnirman, A. (2001) · Reviews of Modern Physics · doi:10.1103/revmodphys.73.357 · Cited by 2,510
Research works printed but not linked: 4
- L. K. Grover in Proceedings of the 28th Annual ACM Symposium on the Theory of Computing G. L. Miller Ed. [Association for Computing Machinery (ACM) New York 1996] pp. 212–219.
- Childs A., Quantum Inf. Comput. 5, 456 (2005).
- D. Aharonov M. Ben-Or E. Eban in Proceeding of Innovations in Computer Science (Tsinghua Univ. Press Beijing 2010) p. 453.
- R. Rivest L. Adleman M. Dertouzos in Foundations of Secure Computation R. DeMillo D. Dobkin A. Jones R. Lipton Eds. (Academic Press New York 1978) pp. 169–180.
Cited by
Sorted by citations
Quantum internet: a vision for the road ahead
Wehner, S., Elkouss, D., & Hanson, R. (2018) · Science · doi:10.1126/science.aam9288 · Cited by 2,467
Advances in quantum cryptography
Pirandola, S., Andersen, U. L., Banchi, L., Berta, M., Bunandar, D., Colbeck, R., Englund, D., Gehring, T., Lupo, C., Ottaviani, C., et al. (2020) · Advances in Optics and Photonics · doi:10.1364/aop.361502 · Cited by 2,033
Secure quantum key distribution with realistic devices
Xu, F., Ma, X., Zhang, Q., Lo, H., & Pan, J.-W. (2020) · Reviews of Modern Physics · doi:10.1103/revmodphys.92.025002 · Cited by 1,676
Quantum technologies with optically interfaced solid-state spins
Awschalom, D. D., Hanson, R., Wrachtrup, J., & Zhou, B. B. (2018) · Nature Photonics · doi:10.1038/s41566-018-0232-2 · Cited by 1,096
Cavity-based quantum networks with single atoms and optical photons
Reiserer, A., & Rempe, G. (2015) · Reviews of Modern Physics · doi:10.1103/revmodphys.87.1379 · Cited by 1,028
Metadata
- Authors
- Barz, S., Kashefi, E., Broadbent, A., Fitzsimons, J. F., Zeilinger, A., & Walther, P.
- Affiliations
- University of Vienna (AT)
- University of Edinburgh (GB)
- University of Waterloo (CA)
- University College Dublin (IE)
- Corresponding author
- Barz, Stefanie
- Venue
- Science
- Published
- 2012-01-20
- Volume
- 335
- Issue
- 6066
- Pages
- 303-308
- ISSN
- 0036-8075 (ISSN-L)
- 1095-9203
- OpenAlex
- W2008420411
- Semantic Scholar
- da7ab9e7a904fcb13d5bd91017ae03b88dfa67b6
- Cited by
- 475
- References
- 58
- Citations by year
- 2026: 28 · 2025: 47 · 2024: 36 · 2023: 41 · 2022: 22 · 2021: 52 · 2020: 23 · 2019: 30 · 2018: 31 · 2017: 25 · 2016: 47 · 2015: 26 · 2014: 25 · 2013: 22 · 2012: 17
- FWCI
- 28.13
- Type
- journal article
- Language
- en
- Open access
- green
- arxiv.org
- Locations
- Science (publishedVersion)
- PubMed (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- National University of Singapore (submittedVersion)
- arXiv (Cornell University)
- Bulletin of the American Physical Society
- Funders
- Air Force Office of Scientific Research (FA8655-11-1-3004)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Information and Cryptography
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
- Physical Sciences › Computer Science › Computer Networks and Communications › Cryptography and Data Security
- Keywords
- blind quantum computing, measurement-based quantum computation, cloud quantum computing, quantum privacy, delegated quantum computation, photonic qubits, Deutsch algorithm, Grover's algorithm
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-09, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-09 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Cited sources are checked with a language model’s help (gpt-6-sol).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
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