Enhancement of spontaneous and stimulated emission in the microlaser by standing-wave resonant excitation (original) (raw)

“Amplified Spontaneous Emission” in Micro- and Nanolasers

Atoms, 2021

Amplified Spontaneous Emission is ubiquitous in systems with optical gain and is responsible for many opportunities and shortcomings. Its role in the progression from the simplest form of thermal radiation (single emitter spontaneous emission) all the way to coherent radiation from inverted systems is still an open question. We critically review observations of photon bursts in micro- and nanolasers, in the perspective of currently used measurement techniques, in relation to threshold-related questions for small devices. Corresponding stochastic predictions are analyzed, and contrasted with burst absence in differential models, in light of general phase space properties. A brief discussion on perspectives is offered in the conclusions.

Dynamical control of the emission of a square microlaser via symmetry classes

Physical review, 2018

A major objective in photonics is to tailor the emission properties of microcavities which is usually achieved with specific cavity shapes. Yet, the dynamical change of the emission properties during operation would often be advantageous. The implementation of such a method is still a challenging issue. We present an effective procedure for the dynamical control of the emission lobes which relies on the selection of a specific coherent superposition of degenerate modes belonging to different symmetry classes. It is generally applicable to systems exhibiting pairs of degenerate modes. We explored it experimentally and analytically with organic square microlasers, which emit narrow lobes parallel to their sidewalls. By means of the pump polarization, emission lobes are switched on and off selectively with an extinction ratio better than 1/50.

Dynamical control of square microlaser emission via its symmetry classes

2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2017

A major objective in photonics is to tailor the emission properties of microcavities which is usually achieved with specific cavity shapes. Yet, the dynamical change of the emission properties during operation would often be advantageous. The implementation of such a method is still a challenging issue. We present an effective procedure for the dynamical control of the emission lobes which relies on the selection of a specific coherent superposition of degenerate modes belonging to different symmetry classes. It is generally applicable to systems exhibiting pairs of degenerate modes. We explored it experimentally and analytically with organic square microlasers, which emit narrow lobes parallel to their sidewalls. By means of the pump polarization, emission lobes are switched on and off selectively with an extinction ratio better than 1/50.

Quantum theory of a micromaser operating on the atomic scattering from a resonant standing wave

Physical Review A, 2001

We study the amplification of a resonant standing-wave light field due to the interaction with a beam of monovelocity two-level atoms moving in the Raman-Nath regime and in the Bragg regime. The atomic density is low so that, at most, one atom is inside the cavity at a time. This system is very similar to the well-known micromaser but it is operating in the optical region of the field frequencies. Therefore, the situation corresponds to a microlaser. Unlike the micromaser system, the momentum transfer between the atoms and photons in the microlaser essentially effects the center-of-mass motion of the atoms and the evolution of the field.

Low-threshold microlaser in a high-Q asymmetrical microcavity

Optics Letters, 2009

We experimentally report an asymmetrical spherical microcavity with thermal-induced deformation, in which five-bounce whispering-gallery modes possess not only ultrahigh quality factors ͑Q͒ but also remarkably directional escape emission from the microsphere boundary. With efficient free-space excitation and collection, a low-threshold microlaser is demonstrated and exhibits a highly directional emission. Our measurement agrees well with the theoretical predictions by corrected Fresnel law.

Direct observation of correlations between individual photon emission events of a microcavity laser

Nature, 2009

Lasers are recognized for coherent light emission, the onset of which is reflected in a change of the photon statistics. For many years attempts have been made to measure directly correlations in the individual photon emission events of semiconductor lasers. In previous experiments the temporal decay of these correlations below or at the lasing threshold was considerably faster than the time resolution. We introduce a new measurement technique with a streak camera that overcomes this limitation and provides a track record of the arrival times of individual photons. This allows us to investigate the dynamical evolution of correlations between the individual photon emission events. We apply our studies to micropillar lasers with semiconductor quantum dots as active material that operate in the regime of cavity quantum electrodynamics. While for laser resonators with a low cavity quality factor Q a smooth transition from photon bunching to uncorrelated emission with increasing pumping is demonstrated, we find for high-Q resonators a non-monotonic dependence around the threshold where quantum light emission can occur. We identify regimes of dynamical antibunching of photons in agreement with the predictions of a microscopic theory that includes semiconductor-specific effects.

Dynamical control of square microlaser emission via symmetry classes

Phys. Rev. A, 2018

A major objective in photonics is to tailor the emission properties of microcavities which is usually achieved with specific cavity shapes. Yet the dynamical change of the emission properties during operation would often be advantageous. The implementation of such a method is still a challenging issue. We present an effective procedure for the dynamical control of the emission lobes which relies on the selection of a specific coherent superposition of degenerate modes belonging to different symmetry classes. It is generally applicable to systems exhibiting pairs of degenerate modes. We explored it experimentally and analytically with organic square microlasers, which emit narrow lobes parallel to their sidewalls. By means of the pump polarization, emission lobes are switched on and off selectively with an extinction ratio better than 1/50.

Time-and angle-resolved emission of a microcavity in the non-linear regime

Abstract. We have observed strong oscillations in the time-resolved emission of a semiconductor microcavity, excited non-resonantly with circularly-polarized light pulses. When the cavity is optically driven into a non-linear emission regime, the period of the oscillations amounts to~ 30 ps, independently of the angle of observation.