Semiconductor lasers articles from across Nature Portfolio

Quantum dot (QD) lasers enable intrinsically feedback-tolerant, isolator-free silicon photonic integrated circuits (PICs), eliminating the bulky optical isolators traditionally required to suppress destabilizing reflections. Owing to their delta-function-like density of states, near-zero linewidth enhancement factor, and strong damping, QD lasers sustain stable, high-speed operation without coherence collapse, even under extreme optical feedback. This intrinsic resilience enables direct monolithic integration onto silicon, paving the way for compact, scalable, and CMOS-compatible optical interconnects, while accelerating the transition from laboratory demonstrations to industrial deployment.

By using chaotic vertical-cavity surface-emitting lasers as entropy sources for key generation, a security system based on physical unclonable functions can be created that offers response rates above 500 Gbps with an energy consumption below 1 pJ per bit per laser emitter.

A monolithic mode-locked semiconductor laser with a continuously and widely tunable repetition rate is achieved by using a microwave driving signal that induces a spatiotemporal gain modulation along the entire laser cavity.

A nearly flat broadband quantum walk comb laser is demonstrated in the near-infrared region. A bandwidth of 1.8 THz with a wallplug efficiency of 6% and an ultra-narrow radio frequency linewidth of 1 Hz is achieved at the fundamental repetition rate of 1 GHz.

Photons carrying orbital angular momentum inherit chirality from their twisted wavefront. Here, authors propose a twisted bilayer photonic structure - consisting of semiconductor membrane metasurfaces - where helical wavefronts are combined with non-Hermitian coupling, yielding orbital chiral lasing at telecom wavelengths.

The researchers use gigahertz acoustic waves to control the gain and loss of confined modes of an exciton–polariton condensate in a microcavity, enabling dynamic population transfer. Selective transfer to the ground state yields single-level emission consisting of a spectral frequency comb with gigahertz repetition rates.

Quantum dot (QD) lasers enable intrinsically feedback-tolerant, isolator-free silicon photonic integrated circuits (PICs), eliminating the bulky optical isolators traditionally required to suppress destabilizing reflections. Owing to their delta-function-like density of states, near-zero linewidth enhancement factor, and strong damping, QD lasers sustain stable, high-speed operation without coherence collapse, even under extreme optical feedback. This intrinsic resilience enables direct monolithic integration onto silicon, paving the way for compact, scalable, and CMOS-compatible optical interconnects, while accelerating the transition from laboratory demonstrations to industrial deployment.

Implementing stable laser operation requires optical isolators to protect against destabilizing back-reflection signals. Now, CMOS optical circuits provide a simple and insensitive pathway towards robust protection.

Photon interactions in materials typically create a gaseous bosonic state, which is prone to turbulent behaviour that disrupts coherence. But it is now shown that, using fast-gain processes in a modulated semiconductor laser, light can be stabilized in a liquid-like state, enhancing the coherence of its flow.

Implementing stable lasers often requires complex packaging of multiple devices, such as stand-alone external cavities and isolators. Now, stabilizing and isolating lasers can be realized in a single silicon chip thanks to the Kerr nonlinear effect in a resonator.