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Reststrahlen band and optical bandgaps in semiconducting CrN films

Duc V. Dinh*, Xiang Lü, and Oliver Brandt

Dilara Sen, Olivia Fairlamb, and Frank Peiris

Farihatun Lima, Alexander Bordovalos, Suresh Chaulagain, Ambalanath Shan, and Nikolas J. Podraza

  • *Contact author: duc.vandinh@pdi-berlin.de
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Phys. Rev. Materials 10, 044602 – Published 10 April, 2026Erratum Phys. Rev. Materials 10, 069902 (2026)

DOI: https://doi.org/10.1103/gt8b-1psw

Abstract

We present a comprehensive optical characterization of 200-nm-thick CrN(111) films grown simultaneously on Al2O3(0001) and AlN/Al2O3(0001) using plasma-assisted molecular beam epitaxy. Spectroscopic ellipsometry, spanning the far-infrared to ultraviolet range (0.04–5.5eV), is conducted at room temperature to determine the optical constants n and k of the films. Spectral fits reveal two interband transitions at approximately 0.35 and 0.60 eV. In the infrared range, the ellipsometry data also reveal a pronounced Reststrahlen band stemming from transversal and longitudinal optical phonons at approximately 403 and 629cm−1, respectively. The relative static and high-frequency permittivities are estimated to be about 39 and 15, respectively. A Born effective charge of approximately 2.7, extracted from the far-infrared region, indicates that CrN is partially ionic.

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Erratum

Erratum: Reststrahlen band and optical bandgaps in semiconducting CrN films [Phys. Rev. Materials 10, 044602 (2026)]

Duc V. Dinh, Xiang Lü, Oliver Brandt, Dilara Sen, Olivia Fairlamb, Frank Peiris, Farihatun Lima, Alexander Bordovalos, Suresh Chaulagain, Ambalanath Shan, and Nikolas J. Podraza
Phys. Rev. Materials 10, 069902 (2026)

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References (47)

  1. U. Wiklund, M. Bromark, M. Larsson, P. Hedenqvist, and S. Hogmark, Cracking resistance of thin hard coatings estimated by four-point bending, Surf. Coat. Technol. 91, 57 (1997).
  2. C. Nouveau, M. A. Djouadi, O. Banakh, R. Sanjinés, and F. Lévy, Stress and structure profiles for chromium nitride coatings deposited by R.F. magnetron sputtering, Thin Solid Films 398-399, 490 (2001).
  3. C. Constantin, M. B. Haider, D. Ingram, and A. R. Smith, Metal/semiconductor phase transition in chromium nitride (001) grown by rf-plasma-assisted molecular-beam epitaxy, Appl. Phys. Lett. 85, 6371 (2004).
  4. P. A. Bhobe, A. Chainani, M. Taguchi, T. Takeuchi, R. Eguchi, M. Matsunami, K. Ishizaka, Y. Takata, M. Oura, Y. Senba, H. Ohashi, Y. Nishino, M. Yabashi, K. Tamasaku, T. Ishikawa, K. Takenaka, H. Takagi, and S. Shin, Evidence for a correlated insulator to antiferromagnetic metal transition in CrN, Phys. Rev. Lett. 104, 236404 (2010).
  5. X. Y. Zhang and D. Gall, CrN electronic structure and vibrational modes: An optical analysis, Phys. Rev. B 82, 045116 (2010).
  6. X. Y. Zhang, J. S. Chawla, B. M. Howe, and D. Gall, Variable-range hopping conduction in epitaxial CrN(001), Phys. Rev. B 83, 165205 (2011).
  7. Q. Jin, H. Cheng, Z. Wang, Q. Zhang, S. Lin, M. A. Roldan, J. Zhao, J.-O. Wang, S. Chen, M. He, C. Ge, C. Wang, H.-B. Lu, H. Guo, L. Gu, X. Tong, T. Zhu, S. Wang, H. Yang, K.-J. Jin, et al., Strain-mediated high conductivity in ultrathin antiferromagnetic metallic nitrides, Adv. Mater. 33, 2005920 (2021).
  8. S. Kalal, S. Nayak, S. Sahoo, R. Joshi, R. J. Choudhary, R. Rawat, and M. Gupta, Electronic correlations in epitaxial CrN thin film, Sci. Rep. 13, 15994 (2023).
  9. L. M. Corliss, N. Elliott, and J. M. Hastings, Antiferromagnetic structure of CrN, Phys. Rev. 117, 929 (1960).
  10. J. D. Browne, P. R. Liddell, R. Street, and T. Mills, An investigation of the antiferromagnetic transition of CrN, Phys. Status Solidi A 1, 715 (1970).
  11. P. Subramanya Herle, M. S. Hegde, N. Y. Vasathacharya, S. Philip, M. V. Rama Rao, and T. Sripathi, Synthesis of TiN, VN, and CrN from ammonolysis of TiS2, VS2, and Cr2S3, J. Solid State Chem. 134, 120 (1997).
  12. A. Ney, R. Rajaram, S. S. P. Parkin, T. Kammermeier, and S. Dhar, Magnetic properties of epitaxial CrN films, Appl. Phys. Lett. 89, 112504 (2006).
  13. B. Biswas, S. Rudra, R. S. Rawat, N. Pandey, S. Acharya, A. Joseph, A. I. K. Pillai, M. Bansal, M. de h-Óra, D. P. Panda, A. B. Dey, F. Bertram, C. Narayana, J. MacManus-Driscoll, T. Maity, M. Garbrecht, and B. Saha, Magnetic stress-driven metal-insulator transition in strongly correlated antiferromagnetic CrN, Phys. Rev. Lett. 131, 126302 (2023).
  14. C. X. Quintela, F. Rivadulla, and J. Rivas, Thermoelectric properties of stoichiometric and hole-doped CrN, Appl. Phys. Lett. 94, 152103 (2009).
  15. C. X. Quintela, B. Rodríguez-González, and F. Rivadulla, Thermoelectric properties of heavy-element doped CrN, Appl. Phys. Lett. 104, 022103 (2014).
  16. O. Jankovský, D. Sedmidubský, Š. Huber, P. Šimek, and Z. Sofer, Synthesis, magnetic and transport properties of oxygen-free CrN ceramics, J. Eur. Ceram. Soc. 34, 4131 (2014).
  17. P. Eklund, S. Kerdsongpanya, and B. Alling, Transition-metal-nitride-based thin films as novel energy harvesting materials, J. Mater. Chem. C 4, 3905 (2016).
  18. D. Pankratova, K. Yusupov, A. Vomiero, S. K. Honnali, R. Boyd, D. Fournier, S. Ekeroth, U. Helmersson, C. Azina, and A. le Febvrier, Enhanced thermoelectric properties by embedding Fe nanoparticles into CrN films for energy harvesting applications, ACS Appl. Nano Mater. 7, 3428 (2024).
  19. D. Gall, C.-S. Shin, R. T. Haasch, I. Petrov, and J. E. Greene, Band gap in epitaxial NaCl-structure CrN(001) layers, J. Appl. Phys. 91, 5882 (2002).
  20. P. A. Anderson, R. J. Kinsey, S. M. Durbin, A. Markwitz, V. J. Kennedy, A. Asadov, W. Gao, and R. J. Reeves, Magnetic and optical properties of the InCrN system, J. Appl. Phys. 98, 043903 (2005).
  21. A. Herwadkar and W. R. L. Lambrecht, Electronic structure of CrN: A borderline Mott insulator, Phys. Rev. B 79, 035125 (2009).
  22. A. Filippetti, W. E. Pickett, and B. M. Klein, Competition between magnetic and structural transitions in CrN, Phys. Rev. B 59, 7043 (1999).
  23. A. S. Botana, F. Tran, V. Pardo, D. Baldomir, and P. Blaha, Electronic structure of CrN: A comparison between different exchange correlation potentials, Phys. Rev. B 85, 235118 (2012).
  24. L. Zhou, F. Körmann, D. Holec, M. Bartosik, B. Grabowski, J. Neugebauer, and P. H. Mayrhofer, Structural stability and thermodynamics of CrN magnetic phases from ab initio calculations and experiment, Phys. Rev. B 90, 184102 (2014).
  25. T. Rojas and S. E. Ulloa, Strain fields and electronic structure of antiferromagnetic CrN, Phys. Rev. B 96, 125203 (2017).
  26. Q. Jin, Z. Wang, Q. Zhang, J. Zhao, H. Cheng, S. Lin, S. Chen, S. Chen, H. Guo, M. He, C. Ge, C. Wang, J.-O. Wang, L. Gu, S. Wang, H. Yang, K.-J. Jin, and E.-J. Guo, Structural twinning-induced insulating phase in CrN (111) films, Phys. Rev. Mater. 5, 023604 (2021).
  27. S. M. Aouadi, D. M. Mihut, M. L. Kuruppu, S. R. Kirkpatrick, and S. L. Rohde, Spectroscopic ellipsometry measurements of chromium nitride coatings, J. Vac. Sci. Technol. A 19, 2800 (2001).
  28. K. C. Maurya, D. Rao, S. Acharya, P. Rao, A. I. K. Pillai, S. K. Selvaraja, M. Garbrecht, and B. Saha, Polar semiconducting scandium nitride as an infrared plasmon and phonon–polaritonic material, Nano Lett. 22, 5182 (2022).
  29. J. D. Caldwell, L. Lindsay, V. Giannini, I. Vurgaftman, T. L. Reinecke, S. A. Maier, and O. J. Glembocki, Low-loss, infrared and terahertz nanophotonics using surface phonon polaritons, Nanophotonics 4, 44 (2014).
  30. S. Foteinopoulou, G. C. R. Devarapu, G. S. Subramania, S. Krishna, and D. Wasserman, Phonon-polaritonics: Enabling powerful capabilities for infrared photonics, Nanophotonics 8, 2129 (2018).
  31. D. V. Dinh, J. Herfort, A. Fiedler, and O. Brandt, Carrier transport and electrical bandgaps in epitaxial CrN layers, Adv. Electron. Mater. (2026), e70364, https://doi.org/10.1002/aelm.70364.
  32. D. V. Dinh, J. Lähnemann, L. Geelhaar, and O. Brandt, Lattice parameters of ScxAl1−xN layers grown on GaN(0001) by plasma-assisted molecular beam epitaxy, Appl. Phys. Lett. 122, 152103 (2023).
  33. See Supplemental Material at http://link.aps.org/supplemental/10.1103/gt8b-1psw for (1) XRD scans and thickness simulation of the films; (2) XRD measurements used for the calculation of the lattice constant; (3) Azimuthal scans used to determine epitaxial relationships and  (4) spectra and their fitting for the film across the entire spectral range; and (5) FTIR transmittance spectra of the film.
  34. D. Aspnes, Modulation spectroscopy/electric field effects on the dielectric function of semiconductors, in Handbook on Semiconductors: Volume 2. Optical Properties of Solids (North-Holland, Amsterdam, 1980).
  35. H. Fujiwara, in Spectroscopic Ellipsometry (Wiley, Chichester, UK, 2007), Chap. 5, pp. 147–207.
  36. J. Klein, L. Kampermann, B. Mockenhaupt, M. Behrens, J. Strunk, and G. Bacher, Limitations of the tauc plot method, Adv. Funct. Mater. 33, 2304523 (2023).
  37. H. Rubens and E. Aschkinass, Die reststrahlen von steinsalz und sylvin, Ann. Phys. 301, 241 (1898).
  38. S. Adachi, The reststrahlen region, in Optical Properties of Crystalline and Amorphous Semiconductors (Springer, Boston, MA, 1999), pp. 33–62.
  39. D. V. Dinh, F. Peiris, J. Lähnemann, and O. Brandt, Optical properties of ScN layers grown on Al2O3(0001) by plasma-assisted molecular beam epitaxy, Appl. Phys. Lett. 123, 112102 (2023).
  40. C. X. Quintela, J. P. Podkaminer, M. N. Luckyanova, T. R. Paudel, E. L. Thies, D. A. Hillsberry, D. A. Tenne, E. Y. Tsymbal, G. Chen, C.-B. Eom, and F. Rivadulla, Epitaxial CrN thin films with high thermoelectric figure of merit, Adv. Mater. 27, 3032 (2015).
  41. M. Ramsteiner, O. Brandt, and K. H. Ploog, Overdamped excitations of the free electron gas in GaN layers studied by Raman spectroscopy, Phys. Rev. B 58, 1118 (1998).
  42. M. Born and K. Huang, Dynamical Theory of Crystal Lattices (Clarendon Press, Oxford, UK, 1954).
  43. R. H. Lyddane, R. G. Sachs, and E. Teller, On the polar vibrations of alkali halides, Phys. Rev. 59, 673 (1941).
  44. E. F. Schubert, Characterization techniques, in Doping in III-V Semiconductors (Cambridge University Press, Cambridge, UK, 1993), p. 512.
  45. M. Schubert, Infrared model dielectric functions, in Infrared Ellipsometry on Semiconductor Layer Structures (Springer, Berlin, 2005), Chap, 3, pp. 31–43.
  46. X. Gonze and C. Lee, Dynamical matrices, Born effective charges, dielectric permittivity tensors, and interatomic force constants from density-functional perturbation theory, Phys. Rev. B 55, 10355 (1997).
  47. M. D. Fontana, G. Metrat, J. L. Servoin, and F. Gervais, Infrared spectroscopy in KNbO3 through the successive ferroelectric phase transitions, J. Phys. C: Solid State Phys. 17, 483 (1984).

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Phys. Rev. Materials 10, 044602– Published 10 April, 2026
  • Received 1 December 2025
  • Revised 4 February 2026
  • Accepted 23 March 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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