Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userPhase locking of coupled lasers with many longitudinal modes
222
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Detailed experimental and theoretical investigations on two coupled fiber lasers, each with many longitudinal modes, reveal that the behavior of the longitudinal modes depends on both the coupling strength as well as the detuning between them. For low to moderate coupling strength only longitudinal modes which are common for both lasers phase-lock while those that are not common gradually disappear. For larger coupling strengths, the longitudinal modes that are not common reappear and phase-lock. When the coupling strength approaches unity the coupled lasers behave as a single long cavity with correspondingly denser longitudinal modes. Finally, we show that the gradual increase in phase-locking as a function of the coupling strength results from competition between phase-locked and non phase-locked longitudinal modes.
rate research
Read More
A unique approach for steady in-phase locking of lasers in an array, regardless of the array geometry, position, orientation, period or size, is presented. The approach relies on the insertion of an intra-cavity Gaussian aperture in the far-field plane of the laser array. Steady in-phase locking of $90$ lasers, whose far-field patterns are comprised of sharp spots with extremely high power density, was obtained for various array geometries, even in the presence of near-degenerate solutions, geometric frustration or superimposed independent longitudinal modes. The internal phase structures of the lasers can also be suppressed so as to obtain pure Gaussian mode laser outputs with uniform phase and overall high beam quality. The approach could potentially improve the performances of recently developed laser simulators that are used for solving various computational problems.
We report on the phase-locking of two diode lasers based on self-seeded tapered amplifiers. In these lasers, a reduction of linewidth is achieved using narrow-band high-transmission interference filters for frequency selection. The lasers combine a compact design with a Lorentzian linewidth below 200 kHz at an output power of 300 mW. We characterize the phase noise of the phase-locked laser system and study its potential for coherent beam-splitting in atom interferometers.
A laser is based on the electromagnetic modes of its resonator, which provides the feedback required for oscillation. Enormous progress has been made in controlling the interactions of longitudinal modes in lasers with a single transverse mode. For example, the field of ultrafast science has been built on lasers that lock many longitudinal modes together to form ultrashort light pulses. However, coherent superposition of many longitudinal and transverse modes in a laser has received little attention. The multitude of disparate frequency spacings, strong dispersions, and complex nonlinear interactions among modes greatly favor decoherence over the emergence of order. Here we report the locking of multiple transverse and longitudinal modes in fiber lasers to generate ultrafast spatiotemporal pulses. We construct multimode fiber cavities using graded-index multimode fiber (GRIN MMF). This causes spatial and longitudinal mode dispersions to be comparable. These dispersions are counteracted by strong intracavity spatial and spectral filtering. Under these conditions, we achieve spatiotemporal, or multimode (MM), mode-locking. A variety of other multimode nonlinear dynamical processes can also be observed. Multimode fiber lasers thus open new directions in studies of three-dimensional nonlinear wave propagation. Lasers that generate controllable spatiotemporal fields, with orders-of-magnitude increases in peak power over existing designs, should be possible. These should increase laser utility in many established applications and facilitate new ones.
We present a systematic analysis of the stationary regimes of nonlinear parity-time(PT) symmetric laser composed of two coupled fiber cavities. We find that power-dependent nonlinear phase shifters broaden regions of existence of both PT-symmetric and PT-broken modes, and can facilitate transitions between modes of different types. We show the existence of non-stationary regimes and demonstrate an ambiguity of the transition process for some of the unstable states. We also identify the presence of higher-order stationary modes, which return to the initial state periodically after a certain number of round-trips.
Motivated by recent experiments, which demonstrated lasing and cooling of the electromagnetic field in an electrical resonator coupled to a superconducting qubit, we study the phase coherence and diffusion of the system in the lasing state. We also discuss phase locking and synchronization induced by an additional {sl ac} driving of the resonator. We extend earlier work to account for the strong qubit-resonator coupling and to include the effects of low-frequency qubits noise. We show that the strong coupling may lead to a double peak structure of the spectrum, while the shape and width are determined to the low-frequency noise.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
