Patent ID: 8264693

Claim:
A method of measuring at least one property including a magnetic property of target material, the method comprising the steps of: generating a pump pulse train having one or more pump pulses at a repetition rate along a first propagation path, each pump pulse having a pulse energy density, a laser wavelength within a range of laser wavelengths, and a pulse duration; irradiating the target material with at least a portion of the one or more pump pulses focused into at least one spot having a spot shape and size so as to cause transient perturbation in the target material; generating at least one probe pulse train having one or more probe pulses at a repetition rate along a second propagation path, each probe pulse having a pulse energy density, a laser wavelength within a range of laser wavelengths, and a pulse duration; irradiating the target material with at least a portion of the one or more probe pulses focused into at least one spot having a spot shape and size to obtain one or more reflected probe pulses which are modulated based on the transient perturbation; electronically controlling a time interval between a time at which the target material is irradiated by each of the focused pump pulses and a time at which the target material is irradiated by each of its corresponding focused probe pulses wherein the time interval is capable of being controlled to be greater than or less than 1 ns; detecting each modulated probe pulse to obtain one or more corresponding signals; and processing the one or more signals to obtain one or more measurement signals which represents the at least one property including the magnetic property of the target material.