arXiv subjects

Lucía Olano-Vegas

Publications and source records attributed to Lucía Olano-Vegas.

3 recordsLinked to original sources

arXiv2026

A new helical InSeI polymorph: crystal structure and polarized Raman spectroscopy study

Tetragonal InSeI is an interesting low-dimensional metal chalcohalide due to its composition and anisotropic crystal structure composed of helical chains, which give rise to optoelectronic properties with potential application in photodetectors, optical thermometers, and spintronic devices. However, experimental works lack on the study of its anisotropic or chiral behavior. Here we present the crystal structure of an unreported InSeI polymorph and study its lattice dynamics in bulk crystals and exfoliated nanowires by polarized Raman spectroscopy for two non-equivalent crystallographic planes. We determine the orientation of the helical chains and distinguish between crystallographic planes by linearly polarized measurements, evaluating the angle-dependent intensity of the modes, which allows assigning each mode to its representation. Circularly polarized Raman measurements do not reveal chiral phonons, despite the helical chains and anisotropic crystal structure. These results offer insight into the crystal structure of InSeI, which is fundamental for the fabrication of orientation-dependent optoelectronic and spintronic devices.

cond-mat.mtrl-sci↗

arXiv2026

Engineering magnetism in hybrid organic-inorganic metal halide perovskites

The chemical and structural flexibility of hybrid organic-inorganic metal halide perovskites (HOIPs) provides an ideal platform for engineering not only their well-studied optical properties, but also their magnetic ones. In this review we present HOIPs from a new perspective, turning the attention to their magnetic properties and their potential as new class of on-demand low-dimensional magnetic materials. Focusing on HOIPs containing transition metals, we comprehensively present the progress that has been made in preparing, understanding and exploring magnetic HOIPs. First, we briefly introduce HOIPs in terms of composition and crystal structure and examine the synthesis protocols commonly used to prepare those showing magnetic properties. Then, we present their rich magnetic behavior and phenomenology; discuss their origin and guidelines for tuning them by changing the perovskite phase, chemical composition and dimensionality; and showcase their potential application in magneto-optoelectronics and spintronics. Finally, we describe the current challenges in the field, such as their integration into devices, as well as the emerging possibilities of moving from magnetic doping to pure transition metal-based HOIPs, which will motivate further studies in the future.

cond-mat.mtrl-sci↗

arXiv2024

Unveiling intrinsic bulk photovoltaic effect in atomically thin ReS2

The bulk photovoltaic effect (BPVE) offers a promising avenue to surpass the efficiency limitations of current solar cell technology. However, disentangling intrinsic and extrinsic contributions to photocurrent remains a significant challenge. Here, we fabricate high-quality, lateral devices based on atomically thin ReS2 with minimal contact resistance, providing an optimal platform for distinguishing intrinsic bulk photovoltaic signals from other extrinsic photocurrent contributions originating from interfacial effects. Our devices exhibit large bulk photovoltaic performance with intrinsic responsivities of 1 mA/W in the visible range, without the need for external tuning knobs such as strain engineering. Our experimental findings are supported by theoretical calculations. Furthermore, our approach can be extrapolated to investigate the intrinsic BPVE in other non-centrosymmetric van der Waals materials, paving the way for a new generation of efficient light-harvesting devices.

cond-mat.mes-hall↗