Experimental Implementation of Fast Quantum Searching
Abstract
Using nuclear magnetic resonance techniques with a solution of chloroform molecules we implement Grover's search algorithm for a system with four states. By performing a tomographic reconstruction of the density matrix during the computation good agreement is seen between theory and experiment. This provides the first complete experimental demonstration of loading an initial state into a quantum computer, performing a computation requiring fewer steps than on a classical computer, and then reading out the final state.
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Prototype quantum computers that store and process information on individual atoms have already been demonstrated.
“Although an Avogadro scale computer that can act on 10 23 bits might seem implausible, prototype quantum computers that store and process information on individual atoms have already been demonstrated 64 -65 , 76 -80 .”
From Ultimate physical limits to computation (2000) · cites this paper as [80]
Recently constructed quantum microcomputers use one quantum degree of freedom for each bit and operate at the Heisenberg limit Δt = π hbar/2ΔE for the time needed to flip a bit.
“The laws of physics do not require redundancy to perform logical operations: recently constructed quantum microcomputers use one quantum degree of freedom for each bit and operate at the Heisenberg limit ∆ t = π ¯ h/ 2∆ E for the time needed to flip a bit 64 -65 , 76 -80 .”
From Ultimate physical limits to computation (2000) · cites this paper as [80]
Contemporary quantum microcomputers constructed using nuclear magnetic resonance operate at the limits of speed and memory space described above.
“In fact, contemporary quantum 'microcomputers' such as those constructed using nuclear magnetic resonance 76 -80 do indeed operate at the limits of speed and memory space described above.”
From Ultimate physical limits to computation (2000) · cites this paper as [80]
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- Authors
- Chuang, I. L., Gershenfeld, N., & Kubinec, M.
- Affiliations
- IBM Research - Almaden (US)
- MIT Media Lab (US)
- University of California, Berkeley (US)
- Venue
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Published
- 1998-04-13
- Volume
- 80
- Issue
- 15
- Pages
- 3408-3411
- ISSN
- 0031-9007 (ISSN-L)
- 1079-7114
- OpenAlex
- W1996519437
- Semantic Scholar
- 6c055053f4f1605fdc0bd474c7a350dcd01f627d
- Cited by
- 707
- References
- 9
- Citations by year
- 2026: 15 · 2025: 23 · 2024: 16 · 2023: 26 · 2022: 22 · 2021: 26 · 2020: 23 · 2019: 14 · 2018: 8 · 2017: 10 · 2016: 15 · 2015: 14 · 2014: 11 · 2013: 12 · 2012: 15
- FWCI
- 72.11
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Physical Review Letters (publishedVersion)
- Topics
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Information and Cryptography
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Keywords
- Grover's algorithm, quantum search, chloroform, four-qubit systems, quantum advantage
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