Semiconductor Spin Qubits

Subgroup Description

We have several ongoing projects related to the study of single spins in quantum dots as candidate qubits. We are interested in learning how to accurately control and read out the spin of a single electron or hole in a single quantum dot. We also study the coherence properties of spin qubits (meaning roughly how long our qubits can store information), and investigate mechanisms for increasing the coherence time. Furthermore, we are working on the implementation of a spin-photon interface, which would allow quantum information from a spin qubit to be transferred to the polarization of a photon. This work is a precursor to forming entanglement between remote spins.

The long-term vision for our work is outlined in papers by Ladd et al. [http://dx.doi.org/10.1088/1367-2630/8/9/184] and Jones et al. [http://arxiv.org/abs/1010.5022].

Figure 1. Ladd et al. discuss the potential design of a quantum repeater that may be implemented using some of the techniques we are developing. In particular, the repeater requires fault-tolerant operation of a set of quantum memories and light-matter interfaces.

Figure 2. Jones et al. discuss how our control and measurement techniques could be used in a system with many quantum dots to form a fast, large-scale, fault-tolerant quantum computer.

Projects

Ultrafast Optical Control of Spin Qubits

Optical Spin Echo

Nuclear Bath Interaction with a Spin Qubit

Nuclear Spin Detection in Silicon

Donor-bound Electron Spin Qubit in ZnSe

Semiconductor Indistinguishable Single Photon Source

Subgroup Members

Kristiaan De Greve

Darin Sleiter

Peter McMahon

Leo Yu

Zhe Wang

Prof. Yoshihisa Yamamoto

Recent Alumni

Dr. Thaddeus Ladd

Dr. David Press

External Collaborators

Christian Schneider (Universität Würzburg, Germany)

Sven Höfling (Universität Würzburg, Germany)

Prof. Alfred Forchel (Universität Würzburg, Germany)