Simple technique for determining the refractive index of phase-change materials using near-infrared reflectometry

被引：0

作者：

Gemo E. ^{[1
]}

Kesava S.V. ^{[2
]}

de Galarreta C.R. ^{[1
]}

Trimby L. ^{[1
]}

Carrillo S.G.-C. ^{[1
]}

Riede M. ^{[2
]}

Baldycheva A. ^{[1
]}

Alexeev A. ^{[1
]}

Wright C.D. ^{[1
]}

机构：

[1] Department of Engineering, University of Exeter, Exeter

[2] Department of Physics, University of Oxford, Oxford

来源：

Optical Materials Express | 2020年 / 10卷 / 07期

基金：

英国工程与自然科学研究理事会; 欧盟地平线“2020”;

关键词：

D O I：

10.1364/OME.10.001675

中图分类号：

学科分类号：

摘要：

Phase-change materials, such as the well-known ternary alloy Ge2Sb2Te5, are essential to many types of photonic devices, from re-writeable optical disk memories to more recent developments such as phase-change displays, reconfigurable optical metasurfaces, and integrated phase-change photonic devices and systems. The successful design and development of such applications and devices requires accurate knowledge of the complex refractive index of the phase-change material being used. To this end, it is common practice to rely on published experimental refractive index data. However, published values can vary quite significantly for notionally the same composition, no doubt due to variations in fabrication/deposition processes. Rather than rely on published data, a more reliable approach to index determination is to measure the properties of as-fabricated films, and this is usually carried out using specialized and dedicated ellipsometric equipment. In this paper, we propose a simple and effective alternative to ellipsometry, based on spectroscopic reflectance measurements of Fabry-Perot phase-change nanocavities. We describe this alternative approach in detail, apply it to measurement of the complex index of the archetypal phase-change materials Ge2Sb2Te5 and GeTe, and compare the results to those obtained using conventional ellipsometry, where we find good agreement. © 2020.

引用

页码：1675 / 1686

页数：11

共 40 条

[1]

Hosseini P., Wright C.D., Bhaskaran H., An optoelectronic framework enabled by low-dimensional phase-change films, Nature, 511, 7508, pp. 206-211, (2014)

[2]

Wuttig M., Bhaskaran H., Taubner T., Phase-Change materials for non-volatile photonic applications, Nat. Photonics, 11, 8, pp. 465-476, (2017)

[3]

Garcia-Cuevas Carrillo S., Trimby L., Au Y.-Y., Nagareddy K., Rodriguez-Hernandez G., Hosseini P., Rios C., Bhaskaran H., Wright C.D., A Nonvolatile Phase-Change Metamaterial Color Display, Adv. Opt. Mater, 7, 18, (2019)

[4]

Garcia-Cuevas Carrillo S., Alexeev A.M., Au Y.-Y., Wright C.D., Reconfigurable phase-change meta-absorbers with on-demand quality factor control, Opt. Express, 26, 20, pp. 25567-25581, (2018)

[5]

Ruiz de Galarreta C., Alexeev A.M., Au Y.-Y., Lopez-Garcia M., Klemm M., Cryan M., Bertolotti J., Wright C.D., Nonvolatile reconfigurable phase-change metadevices for beam steering in the near infrared, Adv. Funct. Mater, 28, 10, (2018)

[6]

Gemo E., Garcia-Cuevas Carrillo S., Ruiz de Galarreta C., Baldycheva A., Hayat H., Youngblood N., Bhaskaran H., Pernice W.H.P., Wright C.D., Plasmonically-enhanced all-optical integrated phase-change memory, Opt. Express, 27, 17, pp. 24724-24737, (2019)

[7]

Feldmann J., Youngblood N., Wright C.D., Bhaskaran H., Pernice W.H.P., All-optical spiking neurosynaptic networks with self-learning capabilities, Nature, 569, 7755, pp. 208-214, (2019)

[8]

Ros C., Youngblood N., Cheng Z., Le Gallo M., Pernice W.H.P., Wright C.D., Sebastian A., Bhaskaran H., In-memory computing on a photonic platform, Sci. Adv, 5, 2, (2019)

[9]

Wuttig M., Yamada N., Phase-change materials for rewriteable data storage, Nat. Mater, 6, 11, pp. 824-832, (2007)

[10]

Burr G.W., Kim S., Brightsky M., Sebastian A., Lung H.-L., Cheng H.-Y., Cortes N.E.S., Wu J.Y., Pozidis H., Lam C., Recent progress in Phase change memory technology, IEEE J. Emerg. Sel. Topics Circuits Syst, 6, 2, pp. 146-162, (2016)

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