MTime: April 16, 2017
Source: College of Science and Technology
Publisher： JNU News Center

Fu Shenghe, associate professor in JNU's photoelectrical engineering department, has published a research paper as first author in the world-renowned physics journal Physical Review Letters after leading his research team to breakthroughs in researching new photoelectrical materials and laser technologies.

Physical Review Letters has reported many scientific discoveries and theories in the history of physics, including the discoveries of X-rays, electrons and electron charge; Einstein’s theories of relativity and the photoelectric effect; Schroedinger quantum theory; electron wave theory; laser theory; superconductivity theory and Bose-Einstein condensate. Publication of Prof. Fu’s paper indicates that JNU’s scientific research level in this field has significantly improved and is an important achievement for the program of building a high-level university.

The paper reports on the theoretical and experimental study of the generation of propagating waveguide modes on the water surface. These propagating modes are modulated in the transverse direction in a manner that satisfies boundary conditions on the walls of the water tank. It is shown that the propagating modes possess both anomalous and normal dispersion regimes, in contrast to the extensively studied zero mode that, in the case of deep water, only has normal dispersion with a fixed frequency independent dispersion coefficient. Importantly, by using a carrier frequency at which the group velocity dispersion crosses zero, a linear nonspreading and shape-preserving wave packet is observed. By increasing the wave steepness, nonlinear effects become pronounced, thereby enabling the first observation of linearly chirped parabolic water wave pulses in the anomalous dispersion regime. This parabolic wave maintains its linear frequency chirp and does not experience wave breaking during propagation.

Link to the paper:
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.144501