Dr. Muhammad Anisuzzaman Talukder, Assistant Professor, Department of EEE, BUET has been Awarded a United States Patent
Dr. Muhammad Anisuzzaman Talukder, Assistant Professor, Department of EEE, BUET has been awarded a United States Patent (Pantent No.: US 7,940,818 B2) on May 10, 2011 for his invention of “Passively Modelocked Quantum Cascade Lasers.” The invention claims a novel technique to generate ultra-short (on the order of 100 femtosecond) pulses from mid-infrared quantum cascade lasers, which is fundamentally prohibitive due to the inherent properties of quantum cascade lasers. This invention shows that self-induced transparency effect can be used to modelock quantum cascade lasers and stable pulses on the order of 100 femtosecond can be created. To achieve modelocking using self-induced transparency effect, absorbing periods are grown interleaved with the conventional gain periods in right numbers and with right dipole moment ratios with the gain periods. The outcome of this research has been published in a number of very reputed journals, including Physical Review Letters, Physical Review A, Applied Physics Letters, and Optics Express.
Dr. Anis’s invention opens a path to generate sup-ps pulses in the molecular finger-print mid-infrared region. These mid-infrared pulses with very high instantaneous power can be used for remote sensing of trace and hazardous gases for environmental safety and medical applications. These pulses are also the key elements for many important applications such as nonlinear frequency conversion, time-resolved measurements, coherent control, and frequency combs.