Outputs (76)

Molecular dynamics calculations of the thermal expansion properties and melting points of Si and Ge (2006)
Journal Article
Timon, V., Brand, S., Clark, S., & Abram, R. (2006). Molecular dynamics calculations of the thermal expansion properties and melting points of Si and Ge. Journal of Physics: Condensed Matter, 18(13), 3489-3498. https://doi.org/10.1088/0953-8984/18/13/016

The thermal expansion properties and melting points of silicon and germanium are calculated using molecular dynamics simulations within the density functional theory framework. An isothermal–isobaric (NPT) ensemble is considered in a periodic system... Read More about Molecular dynamics calculations of the thermal expansion properties and melting points of Si and Ge.

Screened-exchange stress tensor in density functional theory (2006)
Journal Article
Gibson, M., Brand, S., & Clark, S. (2006). Screened-exchange stress tensor in density functional theory. Physical review B, 73(12), Article 125120. https://doi.org/10.1103/physrevb.73.125120

Properties of two-dimensional photonic crystals with octagonal quasicrystalline unit cells (2006)
Journal Article
Roper, D., Beggs, D., Kaliteevski, M., Brand, S., & Abram, R. (2006). Properties of two-dimensional photonic crystals with octagonal quasicrystalline unit cells. Journal of Modern Optics, 53(3), 407-416. https://doi.org/10.1080/09500340500415076

The bandstructures of two-dimensional photonic crystals with octagonal quasicrystalline unit cells have been calculated. The existence of photonic band-gaps in such structures is demonstrated, and results showing the variation of the spectral positio... Read More about Properties of two-dimensional photonic crystals with octagonal quasicrystalline unit cells.

Stability of the photonic band gap in the presence of disorder (2006)
Journal Article
Kaliteevski, M., Beggs, D., Brand, S., Abram, R., & Nikolaev, V. (2006). Stability of the photonic band gap in the presence of disorder. Physical review B, 73(3), https://doi.org/10.1103/physrevb.73.033106

The photonic eigenmodes near a band gap of a type of one-dimensional disordered photonic crystal have been investigated statistically. For the system considered, it is found that the tail of the density of states entering the band gap is characterize... Read More about Stability of the photonic band gap in the presence of disorder.

First-principles calculations of 2x2 reconstructions of GaN(0001) surfaces involving N, Al, Ga, In, and as atoms (2005)
Journal Article
Timon, V., Brand, S., Clark, S., Gibson, M., & Abram, R. (2005). First-principles calculations of 2x2 reconstructions of GaN(0001) surfaces involving N, Al, Ga, In, and as atoms. Physical review B, 72(3), https://doi.org/10.1103/physrevb.72.035327

The ab initio studies presented here employed a pseudopotential-plane-wave method in order to obtain the minimum-energy configurations of various 22 GaN0001 surfaces involving N, Al, Ga, In, and As atoms. Comparison of the various possible reconstruc... Read More about First-principles calculations of 2x2 reconstructions of GaN(0001) surfaces involving N, Al, Ga, In, and as atoms.

Disorder induced modification of reflection and transmission spectra of a two-dimensional photonic crystal with an incomplete band-gap (2005)
Journal Article
Beggs, D., Kaliteevski, M., Brand, S., Abram, R., Cassagne, D., & Albert, J. (2005). Disorder induced modification of reflection and transmission spectra of a two-dimensional photonic crystal with an incomplete band-gap. Journal of Physics: Condensed Matter, 17(26), 4049-4055. https://doi.org/10.1088/0953-8984/17/26/005

Transmission and reflection of light in disordered two-dimensional photonic crystals with an incomplete photonic band-gap have been modelled for various levels of disorder. It is found that ballistic and scattered light display different behaviours a... Read More about Disorder induced modification of reflection and transmission spectra of a two-dimensional photonic crystal with an incomplete band-gap.

Ab initio dynamics study of poly-para-phenylene vinylene (2005)
Journal Article
Zheng, G., Clark, S., Tulip, P., Brand, S., & Abram, R. (2005). Ab initio dynamics study of poly-para-phenylene vinylene. The Journal of Chemical Physics, 123(2), Article 024904. https://doi.org/10.1063/1.1955516

We present an ab initio dynamics investigation within a density-functional perturbation theory framework of the properties of the conjugated polymer poly-para-phenylene vinylene (PPV) in both the isolated chain and crystalline states. The calculated... Read More about Ab initio dynamics study of poly-para-phenylene vinylene.

Theoretical adlayer surface morphology of wurtzite 2 × 2 reconstructions of the GaN (0001) surface (2005)
Journal Article
Timon, V., Brand, S., Clark, S., & Abram, R. (2005). Theoretical adlayer surface morphology of wurtzite 2 × 2 reconstructions of the GaN (0001) surface. Journal of Physics: Condensed Matter, 17(1), 17-26. https://doi.org/10.1088/0953-8984/17/1/002

In the first-principles calculations presented here we employ a density functional formalism using a pseudopotential plane-wave basis set in order to obtain the minimum energy configurations of various GaN(0001) 2 × 2 surfaces involving N atoms. The... Read More about Theoretical adlayer surface morphology of wurtzite 2 × 2 reconstructions of the GaN (0001) surface.

First-principles calculations of 2×2 reconstructions of GaN surfaces (2005)
Presentation / Conference Contribution
Salinero, V., Gibson, M., Brand, S., Clark, S., & Abram, R. (2004, July). First-principles calculations of 2×2 reconstructions of GaN surfaces. Presented at 27th International Conference on the Physics of Semiconductors : ICPS-27., Flagstaff, Arizona

e GaN and other group III nitrides have great importance in a wide range of technological applications. Difficulty in growing good quality epitaxial GaN currently prevents the full technological potential of this material. The ab initio studies prese... Read More about First-principles calculations of 2×2 reconstructions of GaN surfaces.

Screened Exchange Calculations of Semiconductor Band Structures (2005)
Presentation / Conference Contribution
Gibson, M. C., Clark, S. J., Brand, S., & Abram, R. A. (2004, July). Screened Exchange Calculations of Semiconductor Band Structures. Presented at 27th International Conference on the Physics of Semiconductors : ICPS-27., Flagstaff, Arizona

We have calculated the band structures of several group IV and III-V semiconductors from first principles. The technique we have employed is the screened exchange method, which is an extension of the commonly used Kohn-Sham density functional theory... Read More about Screened Exchange Calculations of Semiconductor Band Structures.