제 목 Planar Optics based on Metasurfaces

강 사 Prof. Federico Capasso (Harvard University)

시 간 2016년 7월 14일 (목요일) 오전 10시 30분

장 소 제1신공학관 301동 202호

Abstract:

The design of fundamental optical components such as lenses, gratings, and holograms has remained essentially unchanged for at least fifty years, relying on textbook refractive and diffractive optics. Subwavelength structured surfaces known as metasurfaces are leading to a fundamental reassessment of such designs with the emergence of optical components that circumvent the limitations of standard ones and with entirely new functionalities such as the ability to shape wavefronts in unprecedented ways. Our formulation of the generalized laws of reflection and refraction for metasurfaces has led us recently to demonstrate ultrathin visible and near-IR dielectric metalenses with diffraction limited focusing that can correct monochromatic and chromatic aberrations without using composite lenses. Using a novel Titanium Oxide atomic layer deposition process along with designs based on the Berry phase we have fabricated high numerical aperture lenses in the red, green and blue which outperform state-of-the art objectives as well as new lenses for chiral imaging. Such lenses can be fabricated using the same processing technology of integrated circuits opening the door to high volume applications such as CMOS camera modules. I will also discuss axicons with wavelength independent focusing and broadband high efficiency holograms in the visible and spin-to-orbital angular momemtum converters which create complex multicharged helical beams. I will conclude by presenting a new approach to polarimetry based on scattering from a single metasurface that has allowed us to measure the Stokes parameters of a light beam, matching the performance of existing state-of-the-art bulky polarimiters.

Biography:

Federico Capasso is the Robert Wallace Professor of Applied Physics at Harvard University, which he joined in 2003 after 27 years at Bell Labs where his career advanced from postdoctoral fellow to Vice President for Physical Research. He has made wide ranging contributions to optics, photonics and nanotechnology, including pioneering the bandgap engineering technique, the invention of the quantum cascade laser, the first measurement of the repulsive Casimir force and more recently seminal research on metasurfaces and their applications, including the generalized Snell’s law and flat aberration-free lenses. He is a member of the National Academy of Sciences, the National Academy of Engineering, a fellow of the American Academy of Arts and Sciences (AAAS) and a foreign member of the Accademia dei Lincei. His awards include the IEEE Edison Medal, the American Physical Society Arthur Schawlow Prize in Laser Science, the King Faisal Prize, the SPIE Gold Medal, the AAAS Rumford Prize, the IEEE Sarnoff Award, the Materials Research Society Medal, the Franklin Institute Wetherill Medal, the European Physical Society Quantum Electronics Prize, the Rank Prize in Optoelectronics, the Optical Society Wood Prize, the Berthold Leibinger Future Prize, the Julius Springer Prize in Applied Physics, the Institute of Physics Duddell Medal, the Jan Czochralski Award for lifetime achievements in Materials Science, and the Gold Medal of the President of Italy for meritorious achievement in science.