Ab-initio determination of porous silicon refractive index confirmed by infrared transmittance measurements of an omnidirectional multilayer reflector

Palavicini, Alessio; Wang, Chumín

doi:10.1007/s00340-018-6938-5

Cited by 5 publications

(2 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, the design of electronic and optical devices based on quantum mechanical calculations has been one of the biggest dreams of physicists and engineers, and the recent advances in RSRM bring it closer because these electronic and optical devices usually contain multiple aperiodic located structural interfaces. For example, first-principle calculations have been used in the multiscale design of omnidirectional dielectric reflectors [221] and Fabry-Perot resonators [222], whose results were experimentally confirmed.…”

Section: Discussionmentioning

confidence: 96%

Real Space Theory for Electron and Phonon Transport in Aperiodic Lattices via Renormalization

Sánchez

Wang

2020

Symmetry

Self Cite

View full text Add to dashboard Cite

Structural defects are inherent in solids at a finite temperature, because they diminish free energies by growing entropy. The arrangement of these defects may display long-range orders, as occurring in quasicrystals, whose hidden structural symmetry could greatly modify the transport of excitations. Moreover, the presence of such defects breaks the translational symmetry and collapses the reciprocal lattice, which has been a standard technique in solid-state physics. An alternative to address such a structural disorder is the real space theory. Nonetheless, solving 1023 coupled Schrödinger equations requires unavailable yottabytes (YB) of memory just for recording the atomic positions. In contrast, the real-space renormalization method (RSRM) uses an iterative procedure with a small number of effective sites in each step, and exponentially lessens the degrees of freedom, but keeps their participation in the final results. In this article, we review aperiodic atomic arrangements with hierarchical symmetry investigated by means of RSRM, as well as their consequences in measurable physical properties, such as electrical and thermal conductivities.

show abstract

Section: Discussionmentioning

confidence: 96%

Real Space Theory for Electron and Phonon Transport in Aperiodic Lattices via Renormalization

Sánchez

Wang

2020

Symmetry

Self Cite

View full text Add to dashboard Cite

show abstract

“…Porous materials are attractive materials for many different sensing applications because of their large internal surface area [ 8 , 9 ], open pores network [ 10 ], and widely tunable refractive index [ 11 ]. Several structures using porous materials, especially porous silicon (PSi), have been demonstrated, such as omnidirectional mirrors [ 12 ], multilayers [ 13 ], microcavities [ 14 ], and waveguides [ 15 ]. The potential application areas of porous materials are mainly in the fields of biotechnology [ 16 ], microelectronics [ 17 ], and energy conversion [ 18 ].…”

Section: Introductionmentioning

confidence: 99%

Theoretical Demonstration of the Interest of Using Porous Germanium to Fabricate Multilayer Vertical Optical Structures for the Detection of SF6 Gas in the Mid-Infrared

Zegadi

Lorrain

Meziani

et al. 2022

Sensors

View full text Add to dashboard Cite

Porous germanium is a promising material for sensing applications in the mid-infrared wavelength range due to its biocompatibility, large internal surface area, open pores network and widely tunable refractive index, as well as its large spectral transparency window ranging from 2 to 15 μm. Multilayers, such as Bragg reflectors and microcavities, based on porous germanium material, are designed and their optical spectra are simulated to enable SF6 gas-sensing applications at a wavelength of 10.55 µm, which corresponds to its major absorption line. The impact of both the number of successive layers and their respective porosity on the multilayer structures reflectance spectrum is investigated while favoring low layer thicknesses and thus the ease of multilayers manufacturing. The suitability of these microcavities for mid-infrared SF6 gas sensing is then numerically assessed. Using an asymmetrical microcavity porous structure, a sensitivity of 0.01%/ppm and a limit of detection (LOD) around 1 ppb for the SF6 gas detection are calculated. Thanks to both the porous nature allowing gases to easily infiltrate the overall structure and Ge mid-infrared optical properties, a theoretical detection limit nearly 1000 times lower than the current state of the art is simulated.

show abstract

Tunning the omnidirectional bandgap of nanoporous silicon using a semi-sinusoidal refractive index profile

Salem,

Abdelaleem,

Nasr

et al. 2024

Appl. Phys. A

View full text Add to dashboard Cite

We report the theoretical comparison of the omnidirectional bandgap in a 1-D photonic crystal using sinusoidal and semi-sinusoidal refractive index profiles. It is found that the corresponding omnidirectional bandgap of the semi-sinusoidal widens and shifts to a higher wavelength range as a function of the asymmetric ratio of semi-sinusoidal profile. The asymmetric ratio plays an essential role in tunning the width of the omnidirectional bandgap due to the changed average refractive index and optical thickness. The semi-sinusoidal refractive index is experimentally achieved by changing the current waveform. Novel omnidirectional nanoporous silicon mirrors with an omnidirectional bandgap covering optical communication wavelength (1550 nm) were fabricated using a semi-sinusoidal current waveform. The experimental analogy was carried out by building up the multilayered dielectric structures of omnidirectional mirrors by anodic etching using a semi-sinusoidal current waveform. The experimental results were compared with the theoretical results investigated by the Transfer matrix method. It was shown that the distorted current profile impacts the quality of the omnidirectional bandgap although it does not affect the porous size range.

show abstract

Ab-initio determination of porous silicon refractive index confirmed by infrared transmittance measurements of an omnidirectional multilayer reflector

Cited by 5 publications

References 20 publications

Real Space Theory for Electron and Phonon Transport in Aperiodic Lattices via Renormalization

Real Space Theory for Electron and Phonon Transport in Aperiodic Lattices via Renormalization

Theoretical Demonstration of the Interest of Using Porous Germanium to Fabricate Multilayer Vertical Optical Structures for the Detection of SF6 Gas in the Mid-Infrared

Tunning the omnidirectional bandgap of nanoporous silicon using a semi-sinusoidal refractive index profile

Contact Info

Product

Resources

About