### Abstract

We consider a system composed of a single artificial atom coupled to a cavity mode. The artificial atom is biased such that the most dominant relaxation process in the system takes the atom from its ground state to its excited state, thus ensuring population inversion. A recent experimental manifestation of this situation was achieved using a voltage-biased superconducting charge qubit. Even under the condition of 'inverted relaxation', lasing action can be suppressed if the 'relaxation' rate is larger than a certain threshold value. Using simple transition-rate arguments and a semiclassical calculation, we derive analytic expressions for the lasing suppression condition and the state of the cavity in both the lasing and suppressed-lasing regimes. The results of numerical calculations agree very well with the analytically derived results. We start by analyzing a simplified two-level-atom model, and we then analyze a three-level-atom model that should describe accurately the recently realized superconducting artificialatom laser.

Original language | English |
---|---|

Article number | 023030 |

Journal | New Journal of Physics |

Volume | 11 |

DOIs | |

Publication status | Published - 17 Feb 2009 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*New Journal of Physics*,

*11*, [023030]. https://doi.org/10.1088/1367-2630/11/2/023030

**Single-artificial-atom lasing using a voltage-biased superconducting charge qubit.** / Ashhab, Sahel; Johansson, J. R.; Zagoskin, A. M.; Nori, Franco.

Research output: Contribution to journal › Article

*New Journal of Physics*, vol. 11, 023030. https://doi.org/10.1088/1367-2630/11/2/023030

}

TY - JOUR

T1 - Single-artificial-atom lasing using a voltage-biased superconducting charge qubit

AU - Ashhab, Sahel

AU - Johansson, J. R.

AU - Zagoskin, A. M.

AU - Nori, Franco

PY - 2009/2/17

Y1 - 2009/2/17

N2 - We consider a system composed of a single artificial atom coupled to a cavity mode. The artificial atom is biased such that the most dominant relaxation process in the system takes the atom from its ground state to its excited state, thus ensuring population inversion. A recent experimental manifestation of this situation was achieved using a voltage-biased superconducting charge qubit. Even under the condition of 'inverted relaxation', lasing action can be suppressed if the 'relaxation' rate is larger than a certain threshold value. Using simple transition-rate arguments and a semiclassical calculation, we derive analytic expressions for the lasing suppression condition and the state of the cavity in both the lasing and suppressed-lasing regimes. The results of numerical calculations agree very well with the analytically derived results. We start by analyzing a simplified two-level-atom model, and we then analyze a three-level-atom model that should describe accurately the recently realized superconducting artificialatom laser.

AB - We consider a system composed of a single artificial atom coupled to a cavity mode. The artificial atom is biased such that the most dominant relaxation process in the system takes the atom from its ground state to its excited state, thus ensuring population inversion. A recent experimental manifestation of this situation was achieved using a voltage-biased superconducting charge qubit. Even under the condition of 'inverted relaxation', lasing action can be suppressed if the 'relaxation' rate is larger than a certain threshold value. Using simple transition-rate arguments and a semiclassical calculation, we derive analytic expressions for the lasing suppression condition and the state of the cavity in both the lasing and suppressed-lasing regimes. The results of numerical calculations agree very well with the analytically derived results. We start by analyzing a simplified two-level-atom model, and we then analyze a three-level-atom model that should describe accurately the recently realized superconducting artificialatom laser.

UR - http://www.scopus.com/inward/record.url?scp=63049118450&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=63049118450&partnerID=8YFLogxK

U2 - 10.1088/1367-2630/11/2/023030

DO - 10.1088/1367-2630/11/2/023030

M3 - Article

VL - 11

JO - New Journal of Physics

JF - New Journal of Physics

SN - 1367-2630

M1 - 023030

ER -