Refractive index database

nk database   |   n2 database   |   about




Optical constants of Ge2Sb2Te5 (Germanium antimony telluride, GST)
Frantz et al. 2024: n,k 0.350–29.6 µm

Wavelength: µm

Complex refractive index (n+ik)[ i ]

n   k   LogX   LogY   eV

Derived optical constants

Conditions & Spec sheet

n_is_absolute: true
wavelength_is_vacuum: true


Amorphous Ge2Sb2Te5.


J. A. Frantz, J. D. Myers, A. Clabeau, R. Y. Bekele, N. Hong, M. A. Vincenti, M. Gandolfi, J. S. Sanghera, Optical constants of germanium antimony telluride (GST) in amorphous, crystalline, and intermediate states, Opt. Mater. Express 13, 3631-3640 (2023) (See supplemental materials)


[CSV - comma separated]   [TXT - tab separated]   [Full database record]


Germanium antimony telluride, Ge2Sb2Te5 (GST)

Germanium antimony telluride (GST) is a phase-change material commonly used in optical data storage and photonic applications due to its remarkable optical properties. This chalcogenide compound exhibits distinct refractive indices in its amorphous and crystalline states, allowing for reversible switching between these phases with the application of heat or laser pulses. This unique characteristic makes GST an essential material in rewritable optical discs, such as DVDs and Blu-rays, as well as in advanced photonic devices. The refractive index of Ge2Sb2Te5 varies significantly with wavelength, making it a versatile material for various optical applications, including waveguides, modulators, and sensors. Additionally, its compatibility with existing semiconductor fabrication processes enables integration into electronic and photonic circuits, paving the way for innovative technologies in data storage and processing.

External links