2results about How to "Lower laser threshold" patented technology

The application discloses application of two-dimensional transition metal boride in a saturable absorber and a laser, and the two-dimensional transition metal boride is Mo 4 / 3 B 2‑x T z The application builds a fiber laser based on two-dimensional Mo 4 / 3 B 2‑x T z , optimizes Mo 4 / 3 B 2‑ x T z saturable absorber and a cavity structure of the fiber laser, and after adjusting pump power and a polarization state in the cavity, self-starting of ultrashort and high-repetition-rate mode-locked pulses is realized.

The application discloses a preparation method of a near-infrared vertical cavity surface laser with low threshold and high gain based on weakly confined quantum dots, and belongs to the technical field of quantum dot lasers. A CdS shell layer is grown on the weakly confined double-tapered CdSe quantum dots, and the thickness of the CdS shell layer is controlled to be 2 layers by controlling the injection amount of dodecanethiol; the CdSe / CdS quantum dots are spin-coated on the high-reflection surface of two Bragg reflectors (DBRs); and the surfaces coated with the quantum dots are close to each other and are spliced to form a vertical cavity surface laser. The vertical cavity surface laser constructed by taking the weakly confined double-tapered hexahedral CdSe / CdS quantum dots as deep red gain material has deep red / near-infrared laser emission of 720 nm, an extremely low laser threshold of 11.23 µJ / cm 2 and an extremely wide gain bandwidth of 670-730 nm.