Pump frequency noise coupling into a microcavity by thermo-optic locking Report Title As thermo-optic locking is widely used to establish a stable frequency detuning between an external laser and a high Q microcavity, it is important to understand how this method affects microcavity temperature and frequency fluctuations. A theoretical analysis of the laser-microcavity frequency fluctuations is...

We demonstrate an ultra-compact and low-threshold thulium microcavity laser that is monolithically integrated on a silicon chip. The integrated microlaser consists of an active thulium-doped aluminum oxide microcavity beside a passive silicon nitride bus waveguide, which enables on-chip pump-input and laser-output coupling. We observe lasing in the wavelength range of 1.8-1.9 μm under 1.6 μm re...

We experimentally demonstrate thermo-optic locking of a semiconductor laser to an integrated toroidal optical microcavity. The lock is maintained for time periods exceeding twelve hours, without requiring any electronic control systems. Fast control is achieved by optical feedback induced by scattering centers within the microcavity, with thermal locking due to optical heating maintaining const...

We report on the fabrication of three-dimensional (3D) high-Q whispering gallery microcavities on a fused silica chip by femtosecond laser microfabriction, enabled by the 3D nature of femtosecond laser direct writing. The processing mainly consists of formation of freestanding microdisks by femtosecond laser direct writing and subsequent wet chemical etching. CO(2) laser annealing is followed t...

The Schawlow-Townes expression for the laser linewidth predicts a substantial cw linewidth enhancement in microcavity lasers, in which a large fraction of spontaneous emission is directed into the lasing mode, in contrast with conventional semiconductor lasers, in which the lasing mode accepts only a tiny fraction of spontaneously emitted photons. By performing a theoretical analysis of rigorou...

A ytterbium-doped silica microcavity laser demonstrates stable laser emission while completely submerged in water. To our knowledge, it is the first solid-state laser whose cavity mode interacts with water. The device generates more than 2 microW of output power. The laser performance is presented, and low-concentration biosensing is discussed as a potential application.

We demonstrate broadband tuning of an optomechanical microcavity optical resonance by exploring the large optomechanical coupling of a double-wheel microcavity and its uniquely low mechanical stiffness. Using a pump laser with only 13 mW at telecom wavelengths we show tuning of the silicon nitride microcavity resonances over 32 nm. This corresponds to a tuning power efficiency of only 400 mW/nm...

We demonstrate an erbium-doped silica toroidal microcavity upconversion laser on a silicon chip lasing in the visible spectral range (510-580 nm). The microcavity is pumped at 1458 nm by a tapered optical fiber coupled to the cavity and the lasing threshold is 690 muW. Lasing is observed at room temperature despite the high nonradiative relaxation rates of Er in pure silica that usually preclud...

We demonstrate locking of an on-chip, high-Q toroidal-cavity to a pump laser using two, distinct methods: coupled power stabilization and wavelength locking of pump laser to the microcavity. In addition to improvements in operation of previously demonstrated micro-Raman and micro-OPO lasers, these techniques have enabled observation of a continuous, cascaded nonlinear process in which photons g...

The gain and loss in a microcavity laser play an important role for the modulation of laser spectrum. We show that dual-wavelength single mode lasing can be achieved in an asymmetric coupled system consisted of two size-mismatched microdisks. The amount of eigenmodes in this coupled-microdisk system is reduced relying on the Vernier effect. Then a single mode is selected to lase by controlling ...