arXiv:1012.3557 · Physical Review Letters

Lasing without Inversion in Circuit Quantum Electrodynamics

Michael Marthaler, Yasuhiro Utsumi, Dmitry S. Golubev, Alexander Shnirman, Gerd Schön

Published Aug 23, 2011• 48 citations

Abstract

We study the photon generation in a transmission line oscillator coupled to a driven qubit in the presence of a dissipative electromagnetic environment. It has been demonstrated previously that a population inversion in the qubit can lead to a lasing state of the oscillator. Here we show that the circuit can also exhibit the effect of "lasing without inversion." It arises since the coupling to the dissipative environment enhances photon emission as compared to absorption, similar to the recoil effect predicted for atomic systems. While the recoil effect is very weak, and so far elusive, the effect described here should be observable with realistic circuits. We analyze the requirements for system parameters and environment.

DOI: 10.1103/physrevlett.107.093901

Related papers

Dissipation in circuit quantum electrodynamics: lasing and cooling of a low-frequency oscillator

Julian Hauss, Arkady Fedorov, Stephan André +6 more

Superconducting qubits coupled to electric or nanomechanical resonators display effects previously studied in quantum electrodynamics (QED) as well as extensions thereof. Here, we consider a driven qubit coupled to a low-frequency oscillator and study the influence of dissipation. When the qubit is driven to perform Rabi oscillations, with Rabi frequency in resonance with the oscillator, the latter can be driven far from equilibrium. Blue detuned driving leads to a population inversion in the qubit and lasing behavior of the oscillator ('single-atom laser'). For red detuning, the qubit cools the oscillator. This behavior persists at the symmetry point where the qubit–oscillator coupling is quadratic and decoherence effects are minimized. Here, the system realizes a 'single-atom-two-photon laser'.

arXiv:0806.1298New Journal of PhysicsSep 30, 200849 citations

Single-Qubit Lasing and Cooling at the Rabi Frequency

Julian Hauss, Arkady Fedorov, Carsten Hutter +2 more

For a superconducting qubit driven to perform Rabi oscillations and coupled to a slow electromagnetic or nanomechanical oscillator we describe previously unexplored quantum optics effects. When the Rabi frequency is tuned to resonance with the oscillator, the latter can be driven far from equilibrium. Blue detuned driving leads to a population inversion in the qubit and a bistability with lasing behavior of the oscillator; for red detuning the qubit cools the oscillator. This behavior persists at the symmetry point where the qubit-oscillator coupling is quadratic and decoherence effects are minimized. There the system realizes a "single-atom-two-photon laser."

arXiv:cond-mat/0701041Physical Review LettersJan 24, 2008120 citations

Few-Qubit Lasing in Circuit QED

Stephan André, Valentina Brosco, Michael Marthaler +2 more

Abstract. Motivated by recent experiments, which demonstrated lasing and cooling of the electromagnetic modes in a resonator coupled to a superconducting qubit, we describe the specific mechanisms creating the population inversion, and we study the spectral properties of these systems in the lasing state. Different levels of the theoretical description, i.e., the semi-classical and the semi-quantum approximation, as well as an analysis based on the full Liouville equation are compared. We extend the usual quantum optics description to account for strong qubit-resonator coupling and include the effects of low-frequency noise. Beyond the lasing transition we find for a singleor few-qubit system the phase diffusion strength to grow with the coupling strength, which in turn deteriorates the lasing state. This may lead to a double peak structure of the power spectrum. PACS numbers: 85.25.Cp 42.50.Pq 03.65.YzLasing in Circuit QED 2 1.

Nov 27, 201220 citations

Few-qubit lasing in circuit QED

Stephan André, Valentina Brosco, Michael Marthaler +2 more

Motivated by recent experiments, which demonstrated lasing and cooling of the electromagnetic modes in a resonator coupled to a superconducting qubit, we describe the specific mechanisms creating the population inversion, and we study the spectral properties of these systems in the lasing state. Different levels of the theoretical description, i.e. the semi-classical and the semi-quantum approximation, as well as an analysis based on the full Liouville equation are compared. We extend the usual quantum optics description to account for strong qubit–resonator coupling and include the effects of low-frequency noise. Beyond the lasing transition we find for a single- or few-qubit system the phase diffusion strength to grow with the coupling strength, which in turn deteriorates the lasing state.

arXiv:0908.4227Physica ScriptaDec 1, 200923 citations

Lasing in circuit quantum electrodynamics with strong noise

Michael Marthaler, Yasuhiro Utsumi, Dmitry S. Golubev

A single artificial atom maser can be realized using a superconducting single electron transistor coupled to an oscillator or a double dot coupled to a transmission-line resonator. The authors suggest a model to describe the possibility of lasing action in various environments under different coupling mechanism.

arXiv:1503.01597Physical Review BMay 26, 20158 citations

Quantum Coherence Effects in Novel Quantum Optical Systems

Eyob Alebachew Sete

Optical response of an active medium can substantially be modified when coherent superpositions of states are excited, that is, when systems display quantum coherence and interference. This has led to fascinating applications in atomic and molecular systems. Examples include coherent population trapping, lasing without inversion, electromagnetically induced transparency, cooperative spontaneous emission, and quantum entanglement. \n \nWe study quantum coherence effects in several quantum optical systems and find interesting applications. We show that quantum coherence can lead to transient Raman lasing and lasing without inversion in short wavelength spectral regions--extreme ultraviolet and x-ray--without the requirement of incoherent pumping. For example, we demonstrate transient Raman lasing at 58.4 nm in Helium atom and transient lasing without inversion at 6.1 nm in Helium-like Boron (triply-ionized Boron). We also investigate dynamical properties of a collective superradiant state prepared by absorption of a single photon when the size of the sample is larger than the radiation wavelength. We show that for large number of atoms such a state, to a good approximation, decays exponentially with a rate proportional to the number of atoms. We also find that the collective frequency shift resulting from repeated emission and reabsorption of short-lived virtual photons is proportional to the number of species in the sample. Furthermore, we examine how a position-dependent excitation phase affects the evolution of entanglement between two dipole-coupled qubits. It turns out that the coherence induced by position-dependent excitation phase slows down the otherwise fast decay of the two-qubit entanglement. We also show that it is possible to entangle two spatially separated and uncoupled qubits via interaction with correlated photons in a cavity quantum electrodynamics setup. Finally, we analyze how quantum coherence can be used to generate continuous-variable entanglement in quantum-beat lasers in steady state and propose possible implementation in quantum lithography.

Oct 19, 20120 citations