Entanglement of Atomic Qubits Using an Optical Frequency Comb

Del Mar Photonics - Newsletter Fall 2010 - Newsletter Winter 2010

Femtosecond lasers and atomic qubits (case study)

We require the femosecond laser to prepare our trapped ions into a motional ground state by generating an optical frequency comb to drive specific ramen transitions. (Phys. Rev. Lett 104, 140501)

Wavelength required is 374.1nm (9 THz detuned from transition.) with a small amount of tunability (+/- 10nm.) Pulse duration of 100fs.
Energy per pulse and output power arnt too much of a concern but ideally need to be as high as possible.

Reference:

APS » Journals » Phys. Rev. Lett. » Volume 104 » Issue 14
Phys. Rev. Lett. 104, 140501 (2010)
Entanglement of Atomic Qubits Using an Optical Frequency Comb (pdf)

D. Hayes*, D. N. Matsukevich, P. Maunz, D. Hucul, Q. Quraishi, S. Olmschenk, W. Campbell, J. Mizrahi, C. Senko, and C. Monroe

Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, Maryland 20742 USA
Received 13 January 2010; published 5 April 2010

We demonstrate the use of an optical frequency comb to coherently control and entangle atomic qubits. A train of off-resonant ultrafast laser pulses is used to efficiently and coherently transfer population between electronic and vibrational states of trapped atomic ions and implement an entangling quantum logic gate with high fidelity. This technique can be extended to the high field regime where operations can be performed faster than the trap frequency. This general approach can be applied to more complex quantum systems, such as large collections of interacting atoms or molecules.

Experimental set-up

The Stokes Raman process driven by frequency combs.

Del Mar Photonics lasers installed at NIST:

Trestles laser installation at NIST Quantum Communication Lab

One of the fundamentally important research areas involved in quantum information science is quantum communications, which deals with the exchange of information encoded in quantum states of matter or quantum bits (known as qubits) between both nearby and distant quantum systems. NIST Quantum Communication project performs core research on the creation, transmission, processing and measurement of optical qubits the quantum states of photons, with particular attention to application to future information technologies.

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