View in EDS

Lasing and antibunching of optical phonons in semiconductor double quantum dots.

Saved in:
Bibliographic Details
Title: Lasing and antibunching of optical phonons in semiconductor double quantum dots.
Authors: Okuyama, R.1 rokuyama@rk.phys.keio.ac.jp, Eto, M.1, Brandes, T.2
Source: New Journal of Physics. 2013, Vol. 15 Issue 8, p1-27. 27p.
Subjects: Phonons, Quantum dots, Optical properties of semiconductors, Charge exchange, Nonequilibrium flow, Electron-phonon interactions, Franck-Condon principle
Abstract: We theoretically propose optical phonon lasing in a double quantum dot (DQD) fabricated on a semiconductor substrate. No additional cavity or resonator is required. An electron in the DQD is found to be coupled to only two longitudinal optical phonon modes that act as a natural cavity. When the energy level spacing in the DQD is tuned to the phonon energy, the electron transfer is accompanied by the emission of the phonon modes. The resulting non-equilibrium motion of electrons and phonons is analyzed by the rate equation approach based on the Born–Markov–Secular approximation. We show that lasing occurs for pumping the DQD via electron tunneling at a rate much larger than the phonon decay rate, whereas phonon antibunching is observed in the opposite regime of slow tunneling. Both effects disappear by an effective thermalization induced by the Franck–Condon effect in a DQD fabricated in a suspended carbon nanotube with strong electron–phonon coupling. [ABSTRACT FROM AUTHOR]
Copyright of New Journal of Physics is the property of IOP Publishing and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:We theoretically propose optical phonon lasing in a double quantum dot (DQD) fabricated on a semiconductor substrate. No additional cavity or resonator is required. An electron in the DQD is found to be coupled to only two longitudinal optical phonon modes that act as a natural cavity. When the energy level spacing in the DQD is tuned to the phonon energy, the electron transfer is accompanied by the emission of the phonon modes. The resulting non-equilibrium motion of electrons and phonons is analyzed by the rate equation approach based on the Born–Markov–Secular approximation. We show that lasing occurs for pumping the DQD via electron tunneling at a rate much larger than the phonon decay rate, whereas phonon antibunching is observed in the opposite regime of slow tunneling. Both effects disappear by an effective thermalization induced by the Franck–Condon effect in a DQD fabricated in a suspended carbon nanotube with strong electron–phonon coupling. [ABSTRACT FROM AUTHOR]
ISSN:13672630
DOI:10.1088/1367-2630/15/8/083032