Abstract: Techniques for reconfiguring spectral features stored in a medium based on a two-state atomic system with transition dipole moment ? includes causing a chirp to pass into the medium. The chirp includes a monochromatic frequency that varies in time by a chirp rate ? over a frequency band BR during a time interval TR. The amplitude AR of the chirp is constant over BR and equal to AR=(hbar/??)?{square root over ((? ln [2/?]))}, The term hbar is reduced Plank's constant, ln is a natural logarithm function, and ? is a ratio of a circumference of a circle to a diameter of the circle. For ?<<1, the atomic-state populations in the two states are inverted. For ?=1, prior atomic-state populations are erased, with final populations equal in the two states, regardless of populations before erasure.

Abstract: Techniques for reconfiguring spectral features stored in a medium based on a two-state atomic system with transition dipole moment ? includes causing a chirp to pass into the medium. The chirp includes a monochromatic frequency that varies in time by a chirp rate ? over a frequency band BR during a time interval TR. The amplitude AR of the chirp is constant over BR and equal to AR=(hbar/??)?{square root over ((? ln [2/?]))}, The term hbar is reduced Plank's constant, ln is a natural logarithm function, and ? is a ratio of a circumference of a circle to a diameter of the circle. For ?<<1, the atomic-state populations in the two states are inverted. For ?=1, prior atomic-state populations are erased, with final populations equal in the two states, regardless of populations before erasure.

Abstract: Techniques for recovering optical spectral features include receiving a detected time series that represents a temporally varying intensity of an optical signal. The optical signal is formed in response to an interaction between a target optical spectrum and a chirped optical field. The chirped optical field is an optical field that has a monochromatic frequency that varies in time. The target optical spectrum is an optical frequency dependent optical property of a material or device. A phase correction factor is determined based only on one or more properties of the chirped optical field. The detected time series is corrected based on the phase correction factor to produce an output time series that reproduces in time a shape of the target spectrum in frequency. These techniques allow for fast measurement of spectral features and eliminate the need for prior knowledge of the target optical spectrum to adjust the chirp rate.

Abstract: Techniques for recovering optical spectral features include receiving a detected time series that represents a temporally varying intensity of an optical signal. The optical signal is formed in response to an interaction between a target optical spectrum and a chirped optical field. The chirped optical field is an optical field that has a monochromatic frequency that varies in time. The target optical spectrum is an optical frequency dependent optical property of a material or device. A phase correction factor is determined based only on one or more properties of the chirped optical field. The detected time series is corrected based on the phase correction factor to produce an output time series that reproduces in time a shape of the target spectrum in frequency. These techniques allow for fast measurement of spectral features and eliminate the need for prior knowledge of the target optical spectrum to adjust the chirp rate.