Lasing-Mode Switch of a Hexagonal ZnO Pyramid Driven by Pressure within a Diamond Anvil Cell

Abstract

Nanolasers are expected to be integrated on chips as miniaturized coherent light sources, and their application is strongly dependent on their lasing behavior. In this work, the lasing behavior of a single hexagonal ZnO pyramid (HZOP) is tailored by tuning the electronic bandgap with pressure. The lasing of the HZOP nanolaser is dominated by a helical whispering-gallery-like mode, and the lasing threshold varies little with increasing pressure. All lasing peaks of HZOP are limited in a spectral prescreen window on the right shoulder of the fluorescence emission and gradually blue-shift accompanied by several abrupt hops with increasing pressure. This feature of a spectral prescreen window originates from the strong coupling between excitons, and the coupling is described by a dispersive complex refractive index. These results provide a new perspective to tune and switch the lasing mode of a nanolaser with precision by the pressure-induced bandgap broadening of a semiconductor.

Optical Behaviors of a Microsized Single-Crystal MAPbI3 Plate under High Pressure

“…In this configuration, a white light source was focused onto the sample with a 20× objective, and the transmitted optical signal was collected by a fiber 200 μm in diameter through a 50× objective where only the optical signal from a circle area of 4 μm diameter is centered at the sample by aligning the fiber port and sample to the center of the iris diaphragm at the image plane. The PL spectrum of the sample under pressure was measured with a homemade fluorescence spectrometer excited by a 532 nm laser as described in our previous work . The MAPbI 3 sample was synthesized with a solution growth method at room temperature consulting a reference .…”

Hydrogen Impurities in ZnO: Shallow Donors in ZnO Semiconductors and Active Sites for Hydrogenation of Carbon Species

“…1 However, unlike traditional semiconductors (such as Si, Ge, and GaAs), WBGS could hardly obtain stable n-type or p-type conductivity with arbitrary carrier concentration. 2,3 For example, ZnO, as an widely attractive WBGS, 4,5 could barely achieve stable p-type conductivity. 6,7 Most researchers have attributed the problem to the uncontrollable high background carrier concentration (BCC).…”

“…During the past decades, dramatic advances have been achieved in the development of wide band gap semiconductors (WBGSs), such as ZnO, GaN, SiC, Ga 2 O 3 , and AlN, for their applications in devices operating under high-temperature and high-voltage conditions . However, unlike traditional semiconductors (such as Si, Ge, and GaAs), WBGS could hardly obtain stable n-type or p-type conductivity with arbitrary carrier concentration. , For example, ZnO, as an widely attractive WBGS, , could barely achieve stable p-type conductivity. , Most researchers have attributed the problem to the uncontrollable high background carrier concentration (BCC) . Considering the various theoretical explanations about high BCC, the most credible one is unintentional doping of hydrogen (UDOH). , The reasons can be described as follows: the oxygen vacancy (V O ) exhibits a deep level and is therefore unlikely to cause high BCC at room temperature.…”

Lasing Behavior of a Single ZnO Nanowire Resonating in Fabry–Perot Mode under Pressure

“…40 However, the lasing threshold of ZnO hexagonal pyramid resonant in whisper-gallery-like mode varies little with pressure increase. 41 As pressure provides us an additional perspective to explore the light−matter strong coupling, more efforts should be paid to explore the lasing behavior of semiconductor micro/ nanostructures under pressure. The energy-wavevector dispersion of exciton−photon polariton could be extracted from the lasing spectrum of ZnO nanowires at low temperature or even at room temperature for CsPbBr 3 .…”