Dual-transverse-mode microsquare lasers with tunable wavelength interval

Abstract

A dual-transverse-mode microsquare laser with a tunable wavelength interval is designed and realized by using a square-ring-patterned contact window. For a 30-μm-side-length microsquare laser with the square-ring width of 4 μm, the wavelength interval varies from 0.25 to 0.37 nm with the intensity ratio less than 2.5 dB as the injection current increases from 89 to 108 mA. Based on the dual-transverse-mode microsquare laser, the microwave signals with the frequencies of 30.56, 32.70, 35.12, and 39.51 GHz and the 3-dB bandwidths of 47, 53, 54, and 47 MHz are obtained at the injection currents of 90, 95, 100, and 105 mA, respectively.

Mode Q factor and lasing spectrum controls for deformed square resonator microlasers with circular sides

“…PACS: 42.55.Sa, 42.55.Px, 42.60.Da, OFC was traditionally generated using femtosecond mode-locked lasers [19, 25, and 26]. The generations of OFC in ultrahigh-Q microresonator have triggered intensive researches of four-wave mixing (FWM) in the microresonator under a continuous-wave laser pumping [27][28][29], and cascaded FWM in the nonlinear optical fiber has also been utilized for generating frequency combs via the pumping of two single-frequency lasers [30][31][32].Recently, square resonators have received a great deal of interest for single-mode lasing and enhancement of mode Q factors [33][34][35][36]. Dual-mode lasing with a tunable wavelength interval was demonstrated for square resonator microlasers with a patterned electrode and a vertex waveguide [33].…”

“…Recently, square resonators have received a great deal of interest for single-mode lasing and enhancement of mode Q factors [33][34][35][36]. Dual-mode lasing with a tunable wavelength interval was demonstrated for square resonator microlasers with a patterned electrode and a vertex waveguide [33].…”

“…Dual-mode lasing with a tunable wavelength interval was demonstrated for square resonator microlasers with a patterned electrode and a vertex waveguide [33]. The large square resonators with a vertex waveguide can have high passive mode Q factors and result in dual-mode lasing simultaneously for the fundamental and first-order transverse modes, as they have near equal mode Q factors accounting the internal absorption loss.…”

“…The large square resonators with a vertex waveguide can have high passive mode Q factors and result in dual-mode lasing simultaneously for the fundamental and first-order transverse modes, as they have near equal mode Q factors accounting the internal absorption loss. However, the mode Q factors are greatly limited by the inevitable radiation loss from the vertices of the square resonator [33,34]. In this letter, we introduce a novel circular-side square resonator (CSR) to modify the mode field patterns and enhance mode Q factors.…”

Sub‐THz wave generation based on a dual wavelength microsquare laser

“…The variation of the lasing wavelength is due primarily to the temperature change, but variation in the peak intensity ratio is significantly low. Slight variation in the wavelength interval (0.03 nm in 20-35 mA range) is useful for fine tuning of the difference frequency, whereas course tuning is possible by selecting the square side length [11]. Fig.…”