Measurement principle

In the PL measurement, multimode optical fibers are used to transmit both the excitation and emission light beams. The PL was excited by tunable lasers and recorded by spectrometers composed of a monochromator (SP500i, Andor, or SR-500, PI) and a charge coupled device CCD (Newton 970P, Andor, or Blaze HRX, PI). For the circular-polarized magneto-PL measurements, left/right-hand circular polarizers, composed of a quarter wave plate and a thin film linear polarizer with the respective angle of +45°/-45° between their axes, were placed in between the optical fiber bundle and sample to detect the left- and right-hand circularly polarized PL, respectively.

In the optical absorption measurements, broadband white light illuminates the sample through a single multimode optical fiber, and the transmitted light is reflected by a retro-reflecting mirror, this reflected light goes through a bundle of optical fibers and arrive the spectrometers the same the those used for the PL measurements.

The samples were placed into a liquid helium cryostat at the centre of a pulsed magnet with the designed peak field of 65 T and pulse duration of 200 ms. In this situation, the CCD was exposed every millisecond synchronous to the time period of the magnetic field pulse. Therefore, hundreds of spectra could be obtained and the field dependent PL or absorption peaks could be analysed.

Measurement Conditions

Wavelength range: 350-1600 nm for optical absorption; 240-980 nm excitation, 300-1600 detection for photoluminescence (PL); 400-800 nm for magnetic circular dichroism and circularly-polarized PL

Magnetic field: 0-60 T, pulse width: 200 ms;

Sample temperature: 2-300 K

Key Contact

Yibo Han

Email：ybhan#hust.edu.cn (Please replace # with @)