In this research, tunability of a commercial diode laser has extended to about more than ± 11 nm using a V-shaped external-cavity fabricated around the laser. Although under normal condition it can be tuned up to about ± 4 nm just by changing its temperature and injection current. Such modified diode laser has then used in a difference-frequency generation (DFG) experimental setup as pump sourc...

we present a detailed analysis of the static tuning characteristics of three section tunable distributed bragg reflector (dbr) laser. the analysis is based on the transfer matrix method (tmm), transmission line and scattering theory. the key feature of the analysis is the use of modified oscillation condition. with the exact oscillation condition, the static tuning characteristics such as thres...

We report a precision and fast wavelength tuning technique demonstrated for a digital-supermode distributed Bragg reflector laser. The laser was dynamically offset-locked to a frequency-stabilized master laser using an optical phase-locked loop, enabling precision fast tuning to and from any frequencies within a ~40-GHz tuning range. The offset frequency noise was suppressed to the statically o...

In order to achieve a continuous tuning of laser emission, the authors designed and fabricated three types of cholesteric liquid crystal cells with pitch gradient, a wedge cell with positive slope, a wedge cell with negative slope, and a parallel cell. The length of the cholesteric liquid crystal pitch could be elongated up to 10 nm, allowing the lasing behavior of continuous or discontinuous s...

We describe first the single mode output intensity of a Brewster windowed laser containing isotope mixtures when the cavity tuning is varied, and then the single mode output of a non-Brewster windowed laser under the influence of an axial magnetic field (Zeeman laser). We show how the central tuning (Lamb) dip in intensity gives way to more complicated tuning dependences such as a double dip. F...

We demonstrate a two-directional tuning method of distributed feedback (DFB) film dye laser devices to achieve high quality lasing and a large tuning range. In this work, we proposed a simple method to fabricate a continuous tunable solid-state dye laser on a flexible Polydimethylsiloxane (PDMS) film. In order to obtain stable and tunable output lasing, the stretching property of the gelatine h...

We demonstrate continuous tuning of a terahertz quantum cascade wire laser over a broad range of ∼330 GHz (∼8.6% of the 3.85 THz center frequency) with single-mode operation. Tuning is achieved with a narrow laser ridge (∼λ(o)/8) and a moveable MEMS (microelectromechanical systems) side object (plunger) to manipulate the transverse optical mode. The frictionless MEMS plunger enables continuous ...

We demonstrate a frequency tunable external cavity terahertz quantum cascade laser using an abutted antireflection-coated silicon lens to reduce facet reflection and as a beam-forming element, with an external grating providing frequency selective optical feedback. Angle tuning of the grating allows a single longitudinal mode of the laser ridge to be selected, resulting in discontinuous tuning ...

Predictable tuning behavior and stable laser operation are both crucial for laser spectroscopy measurements. We report a sampled grating quantum cascade laser (QCL) with high spectral tuning stability over the entire tuning range. We have determined the minimum loss margin required to suppress undesired lasing modes in order to ensure predictable tuning behavior. We have quantified power fluctu...