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Miguel Clemente-León

Publications and source records attributed to Miguel Clemente-León.

3 recordsLinked to original sources

Strain Switching in van der Waals Heterostructures triggered by a Spin-Crossover Metal Organic Framework

Van der Waals heterostructures (vdWHs) combine different layered materials with properties of interest,1 such as two-dimensional (2D) semimetals, semiconductors, magnets or superconductors. These heterostructures provide the possibility of engineering new materials with emergent functionalities that are not accessible in another way. Beyond inorganic 2D materials, layered molecular materials remain still rather unexplored, with only few examples regarding their isolation as atomically thin-layers. By a proper chemical design, the physical properties of these systems can be tuned, as illustrated by the so-called spin-crossover (SCO) compounds, in which a spin transition can be induced by applying external stimuli like light, temperature, pressure or an electric field. Here, we report on vdWHs formed by SCO layers and few-layers graphene, being its properties modified by the strain concomitant to the spin transition. These molecular/inorganic vdWHs represent the deterministic incorporation of bistable molecular layers with other 2D materials of interest in the emergent field of straintronics.

cond-mat.mtrl-sci↗

Ground-state spin blockade in a single-molecule junction

It is known that the quantum-mechanical ground state of a nano-scale junction has a significant impact on its electrical transport properties. This becomes particularly important in transistors consisting of a single molecule. Due to strong electron-electron interactions and the possibility to access ground states with high spins, these systems are eligible hosts of a current-blockade phenomenon called ground-state spin blockade. This effect arises from the inability of a charge carrier to account for the spin difference required to enter the junction, as that process would violate the spin selection rules. Here, we present a direct experimental demonstration of ground-state spin blockade in a high-spin single-molecule transistor. The measured transport characteristics of this device exhibit a complete suppression of resonant transport due to a ground-state spin difference of 3/2 between subsequent charge states. Strikingly, the blockade can be reversibly lifted by driving the system through a magnetic ground-state transition in one charge state, using the tunability offered by both magnetic and electric fields.

cond-mat.mes-hall↗

Peptides as versatile scaffolds for quantum computing

In this work we showcase the potential of peptides as versatile scaffolds for quantum computing and molecular spintronics. In particular, we focus on lanthanide-binding tags, which were originally developed in the field of biotechnology for the study of protein structure and dynamics. Firstly, we demonstrate quantum coherent oscillations in a Neodymium peptidic qubit. Then, employing bacterial biosynthesis, we investigate the possibility of increasing the number of qubits in the same molecular system, with the case studies being a double spin qubit with two distinct coordination environments, and an asymmetric chain of 9 spin qubits with a spin-spin separation of about 2 nm and in an arbitrarily chosen sequence of coordination environments. Finally, we take advantage of biochemical modification for the preparation of paramagnetic, chiral, Self-Assembled Monolayers (SAMs) on Au(111).Our experimental and theoretical characterization shows that this is a promising structure for spintronic applications, and in particular to improve on two state-of-the-art approaches to molecular spin qubits. We conclude with an overview of the challenges and new opportunities opened by this emerging field.

cond-mat.mes-hall↗