Universal unitary gate for single-photon two-qubit states
Open accessAbstract
Upon entangling a spatial binary alternative of a photon with its polarization, one can use single photons to study arbitrary 2-qubit states. Sending the photon through a Mach-Zehnder interferometer, equipped with sets of wave plates that change the polarization, amounts to performing a unitary transformation on the 2-qubit state. We show that any desired unitary gate can be realized by a judicious choice of the parameters of the setup and discuss a number of applications. They include the diagnosis of an unknown 2-qubit state, an optical Grover search, and the realization of a thought experiment invented by Vaidman, Aharonov, and Albert.
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Together with additional phase shifters in the input and output ports, a Mach-Zehnder interferometer can perform an arbitrary SU(2) unitary transformation on a qubit encoded in two spatial modes.
“Together with additional phase shifters in the input and output ports, the Mach-Zehnder interferometer can perform an arbitrary SU(2) unitary transformation on a qubit encoded in the two spatial modes (see, e.g., Englert et al. (2001)).”
From Multiphoton entanglement and interferometry (2012) · cites this paper as Englert et al. (2001)
The qubit pair is carried by a single photon as a polarization qubit and a path qubit.
“The qubit pair is carried by a single photon as a polarization qubit and a path qubit.”
From Experimental proposal for symmetric minimal two-qubit state tomography (2012) · cites this paper as [15]
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Cites
Quantum Mechanics Helps in Searching for a Needle in a Haystack
Grover, L. K. (1997) · Physical Review Letters · doi:10.1103/physrevlett.79.325 · Cited by 4,306 · see citing works
Boschi, D., Branca, S., De Martini, F., Hardy, L., & Popescu, S. (1998) · Physical Review Letters · doi:10.1103/physrevlett.80.1121 · Cited by 1,777 · see citing works
Nonmaximally Entangled States: Production, Characterization, and Utilization
White, A. G., James, D. F. V., Eberhard, P. H., & Kwiat, P. G. (1999) · Physical Review Letters · doi:10.1103/physrevlett.83.3103 · Cited by 511 · see citing works
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Multiphoton entanglement and interferometry
Pan, J.-W., Chen, Z.-B., Lu, C.-Y., Weinfurter, H., Zeilinger, A., & Żukowski, M. (2012) · Reviews of Modern Physics · doi:10.1103/revmodphys.84.777 · Cited by 1,410 · see citing works
Self-citationUniversal unitary gate for single-photon spin-orbit four-dimensional states
Slussarenko, S., Karimi, E., Piccirillo, B., Marrucci, L., & Santamato, E. (2009) · Physical Review A · doi:10.1103/physreva.80.022326 · Cited by 22 · see citing works
Experimental proposal for symmetric minimal two-qubit state tomography
Kalev, A., Shang, J., & Englert, B.-G. (2012) · Physical Review A · doi:10.1103/physreva.85.052115 · Cited by 13 · see citing works
Self-citationQuantum state tomography of photon's polarization and path degrees of freedom
Ferreira, J. L. M., & Bernardo, B. D. L. (2023) · arXiv · doi:10.48550/arxiv.2308.12813 · Cited by 2 · see citing works
“First, we call attention to the fact that creating polarization-path entangled states in a single photon is straightforward [6, 22].”
Background
- Authors
- Englert, B.-G., Kurtsiefer, C., & Weinfurter, H.
- Affiliations
- Universität Ulm (DE)
- Ludwig-Maximilians-Universität München (DE)
- Venue
- Physical Review A
- Publisher
- American Physical Society (APS)
- Published
- 2001-02-07
- Volume
- 63
- Issue
- 3
- ISSN
- 0556-2791 (ISSN-L)
- 1050-2947
- 1094-1622
- OpenAlex
- W2079995539
- Cited by
- 138
- References
- 3
- Citations by year
- 2026: 4 · 2025: 7 · 2024: 6 · 2023: 13 · 2022: 8 · 2021: 3 · 2020: 8 · 2019: 5 · 2018: 4 · 2017: 3 · 2016: 2 · 2015: 7 · 2014: 10 · 2013: 3 · 2012: 6
- FWCI
- 4.84
- Type
- journal article
- Language
- en
- Open access
- green
- arxiv.org
- Locations
- Physical Review A (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- CERN Document Server (European Organization for Nuclear Research) (submittedVersion)
- arXiv (Cornell University)
- Topics
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Information and Cryptography
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Keywords
- two-qubit states, single photons, photon polarization, Mach-Zehnder interferometer, wave plates, quantum state discrimination, quantum computing
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