Linear Optical Quantum Computing in a Single Spatial Mode (original) (raw)

NASA/ADS

;

• Metcalf, Benjamin J. ;
• Spring, Justin B. ;
• Moore, Merritt ;
• Jin, Xian-Min ;
• Barbieri, Marco ;
• Kolthammer, W. Steven ;
• Walmsley, Ian A.

Abstract

We present a scheme for linear optical quantum computing using time-bin-encoded qubits in a single spatial mode. We show methods for single-qubit operations and heralded controlled-phase (cphase) gates, providing a sufficient set of operations for universal quantum computing with the Knill-Laflamme-Milburn [Nature (London) 409, 46 (2001)] scheme. Our protocol is suited to currently available photonic devices and ideally allows arbitrary numbers of qubits to be encoded in the same spatial mode, demonstrating the potential for time-frequency modes to dramatically increase the quantum information capacity of fixed spatial resources. As a test of our scheme, we demonstrate the first entirely single spatial mode implementation of a two-qubit quantum gate and show its operation with an average fidelity of 0.84±0.07.

Publication:

Physical Review Letters

Pub Date:

October 2013

DOI:

10.1103/PhysRevLett.111.150501

arXiv:

arXiv:1305.3592

Bibcode:

2013PhRvL.111o0501H

Keywords:

• 03.67.Lx;
• 42.50.Dv;
• 42.50.Ex;
• Quantum computation;
• Nonclassical states of the electromagnetic field including entangled photon states;
• quantum state engineering and measurements;
• Optical implementations of quantum information processing and transfer;
• Quantum Physics

E-Print:

5 pages, 4 figures. Updated to be consistent with the published version