Towards solid-state quantum repeaters : ultrafast coherent optical control and spin-photon entanglement in charged InAs quantum dots
Abstract/Contents
- Abstract
- This work elaborates on previously established all-optical coherent control techniques of individual InAs quantum dot electron spins, and demonstrates proof-of-principle experiments that should allow the utilization of such quantum dots for future, large-scale quantum repeaters. First, we show how more elaborate, multipulse spin control sequences can markedly increase the fidelity of the individual spin control operations, thereby allowing many more such operations to be concatenated before decoherence destroys the quantum memory. Furthermore, we implemented an ultrafast, gated version of a di erent type of control operation, the so-called geometric phase gate, which is at the basis of many proposals for scalable, multi-qubit gate operations. Next, we realized a new type of quantum memory, based on the optical control of a single hole (pseudo-)spin, that was shown to overcome some of the detrimental e ects of nuclear spin hyper fine interactions, which are assumed to be the predominant sources of decoherence in electron spin-based quantum memories - at the expense, however, of a larger sensitivity to electric field-related noise sources. Finally, we discuss a system-level experiment where the quantum dot electron spin is shown to be entangled with the polarization of a spontaneously emitted photon after ultrafast, time-resolved (few picoseconds) downconversion to a wavelength (1560 nm) that is compatible with low-loss optical fi ber technology. The results of this experiment are two-fold: on the one hand, the spin-photon entanglement provides the necessary light-matter interface for entangling remote memory qubits; on the other hand, the transfer to a low- fiber-loss wavelength enables a signi cant increase in the potential distance range over which such remote entanglement could be established. Together, these two aspects can be seen as a necessary preamble for a future quantum repeater system.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2012 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | De Greve, Kristiaan |
|---|---|
| Associated with | Stanford University, Department of Electrical Engineering |
| Primary advisor | Yamamoto, Yoshihisa |
| Thesis advisor | Yamamoto, Yoshihisa |
| Thesis advisor | Brongersma, Mark L |
| Thesis advisor | Vuckovic, Jelena |
| Advisor | Brongersma, Mark L |
| Advisor | Vuckovic, Jelena |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Kristiaan De Greve. |
|---|---|
| Note | Submitted to the Department of Electrical Engineering. |
| Thesis | Thesis (Ph.D.)--Stanford University, 2012. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2012 by Kristiaan De Greve
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
Also listed in
Loading usage metrics...