Laser terahertz emission microscopy

Murakami, Hironaru; Tonouchi, Masayoshi

doi:10.1016/j.crhy.2007.07.010

Cited by 12 publications

(5 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The detailed LTEM system design and working principles are reported elsewhere. [ 27 ] Figure a illustrates the excitation geometry and THz emission from the MQW sample. The internal bias in the MQW sample was directed perpendicular to the surface, which means that the transient dipole vector was also directed normal to the sample surface.…”

Section: Methodsmentioning

confidence: 99%

Ultrafast Terahertz Nanoseismology of GaInN/GaN Multiple Quantum Wells

Mannan

Bagsican

Yamahara

et al. 2021

Advanced Optical Materials

Self Cite

View full text Add to dashboard Cite

Terahertz (THz) emission spectroscopy and microscopy are applied to investigate the electron and lattice dynamics of Ga0.8In0.2N/GaN multiple quantum wells (MQWs). The THz emission consists of three distinct, differently timed signals, whose physical mechanisms are attributed to i) laser‐induced ultrafast dynamical screening of built‐in bias electric field in MQWs followed by ii) capacitive charge oscillation of the excited carriers and iii) the coherent acoustic phonon (CAP)‐driven polarization surge at the discontinuity between the GaN capping layer and air. These multifunctional optical responses show strong dependence on the quantum well width and photon energies. The temporal separation between the first and third THz pulses corresponds to the propagation of the CAP across the GaN capping layer of the MQW structure, whose thickness can thus be determined with 10 nm precision.

show abstract

Section: Methodsmentioning

confidence: 99%

Ultrafast Terahertz Nanoseismology of GaInN/GaN Multiple Quantum Wells

Mannan

Bagsican

Yamahara

et al. 2021

Advanced Optical Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…LTEM image allowed researchers to visualise the crystalline grain of the solar cell without electrical contact. The authors of [112,113] used this technique to generate terahertz radiation, which was captured in the terahertz image of the solar cell. In this experimental setup, mode-locked lasers that produce femtosecond pulses operating at 800 nm wavelength are used as an optical source.…”

Section: Terahertz Ndtmentioning

confidence: 99%

Multi‐attribute analysis of micro‐defect detection techniques suitable for automated production line of solar wafers and cells

Saleem

Al-Amri

2020

IET Renewable Power Generation

View full text Add to dashboard Cite

Renewable energy is going to play an immensely important role in the coming decades. Hence, the bulk manufacturing of solar panels has seen a renewed interest. For this purpose, it is imperatively important to assess the techniques that can be employed on automated production lines for evaluating the quality of solar wafers and cells. To-date many non-destructive testing methods to access the micro-defects in solar wafers and cells have been developed around the globe; however, not all of them can be applied on a fast-paced production line. In this regard, this study details all the nondestructive evaluating techniques that can be employed on an automated production line. Using a multi-attribute decisionmaking method, a strategic evaluation procedure is developed that can be adopted for the optimum selection of evaluation tools currently available in the market. This study is aimed at young researchers, graduate students and practitioners who want to come up-to-speed regarding the various defects that occur in solar wafers and cells along with the techniques that are currently being adopted to evaluate those defects. Also, future trends in research are highlighted regarding the development of assessment techniques.

show abstract

“…Novel PC systems exhibit some prominent optical properties, such as the superprism effect (super-refraction), 7,8 negative refraction, 9,10 birefringence, 11 self-collimating, 12 slow pulse propagation, 13 and ultra-small optical cavities. 14 Based on these intriguing photonic properties, PC systems have been used as reective coatings, anti-counterfeiting lms, wavelength division multiplexing (WDM) components, color pigments in paints and inks, ultra-low loss photonic integrated circuits, resonator cavities for laser emission, and many other optical devices. [15][16][17][18] PC systems can be divided into one-, two-or three-dimensional photonic band-gap materials based on the periodicity, which can be fabricated at various length scales in two strategies of either bottom-up or top-down.…”

Section: Introductionmentioning

confidence: 99%