Stable single-wavelength emission from fully chaotic microcavity lasers

Abstract

We experimentally and numerically show that single-wavelength emission can be stably observed for a fully chaotic microcavity laser with a stadium shape under continuous wave condition. The emission pattern is asymmetric with respect to the symmetry axes of the laser cavity, and it cannot be explained by a single cavity mode. On the basis of numerical analysis, we interpret such a lasing as the result of frequency-locking interaction among several low-loss cavity modes. Moreover, we experimentally investigate the optical spectral properties of the laser under pulsed-pumping condition, and discuss the pulse-width dependence on the number of lasing modes.

Photonic reservoir computing based on nonlinear wave dynamics at microscale

“…To gain an insight into the computational capability of the microcavity-based RC, the numerical simulation was performed by using the Maxwell-Bloch (MB) model, where the gain medium is modeled as a simple two-level system [26]. Whereas the MB model is a simple model of microcavity lasers, the dynamical lasing phenomena can qualitatively be examined [27,28]. We assumed that the cavity is two-dimensionally extended on a plane, and the electric field is polarized perpendicular to the plane.…”

“…However, we remark that the results presented in this paper do not essentially depends on the cavity size in the normalized form; thus, the real values in actual experiments can be estimated. For example, when L = 100µm, average mode interval ∆ω i /(2π) will be of the order of gigahertz [28]. The photon lifetime τ c in the stadium cavity (without the waveguide) is estimated as 28 ps, and it can be changed by the amplification due to the gain medium.…”

Universal single-mode lasing in fully chaotic two-dimensional microcavity lasers under continuous-wave operation with large pumping power [Invited]

“…where ∆ i represents the lasing oscillation frequency. Note that the lasing mode i depends on the pumping power and can be a fusion of several modes that coalesce by frequency-locking, and separate into individual lasing modes with different frequencies as the pumping power decreases [10,20]. U i is supposed to be normalized.…”

“…A recent experimental study of semiconductor 2D microcavity lasers has demonstrated that single-mode lasing is achieved with a stadium-shaped (i.e., fully chaotic) cavity, while multimode lasing with an elliptic (i.e., nonchaotic) cavity [10,11]. This drastic difference was at-tributed to the difference of spatial modal patterns between the stadium and elliptic cavities.…”

Long-path formation in a deformed microdisk laser

“…7 (d) for the device with r 0 = 50 µm, where the pumping currents were 90 mA in both cases. For chaotic cavity lasers, single-mode lasing has been experimentally observed with CW pumping [25][26][27][28]. For chaotic cavity lasers, it has been numerically observed that nonlinear interactions among modes reduce the number of lasing modes [29], and experimentally observed single-mode lasing is attributed to large modal overlaps between resonant modes [28].…”