Research Samara Lourdes Medina Rivero

Abstract

In the 'Quantum Revolution', a key strategy to advance in the practical implementation of Quantum Science and Technology is the pursuit of new, ideal materials. Smartly tailored organic diradical Molecular Qubits (MQBs), organic molecules with two unpaired electron spins in their ground electronic state, have emerged as platforms for the realization of electron spin qubits. In recent years, a wide variety of organic diradicals have been successfully demonstrated as MQBs through the development of their optical-spin interface. A common feature among these systems is their luminescence, which enables their optical readout. Moreover, these optically addressable diradical MQBs hold great promise for single-entity readout, a major challenge in the field and a crucial step toward practical applications. With the present BOF-SRG project, I aim to design an optimized excitation strategy for the optical readout of organic diradical MQBs. In this context, excitation in the UV spectral region using a high-power laser source is particularly appealing, as it is expected to significantly increase the emission efficiency as well as broaden the applicability of this readout strategy to any emissive organic diradical. I will integrate this excitation source in both PL and ODMR setups to determine the minimum emission intensity required to obtain a measurable ODMR signal. The excitation protocols developed during this project are expected to raise the emission efficiency of the target molecules above the ODMR detection sensitivity, reintegrating low emissive organic diradicals into the 'Quantum Materials' category and enhancing their prospects for single-entity readout.

Researcher(s)

• Promoter: Medina Rivero Samara Lourdes

Research team(s)

• Theory and Spectroscopy of Molecules and Materials (TSM²)

Project type(s)

• Research Project

Abstract

In quantum sensing, capable of sensing small magnetic fields originating from motion of electrons, quantum bits (qubits) are preferably operational at room temperature. Recently, smartly tailored organic Molecular Quantum Bits (MQBs) have emerged as platforms for the realization of electron spin qubits, which bring many advantages such as long coherence times, exact positioning of the qubit and tunability through chemical synthesis and scalability. Yet, the implementation of MQBs is obstructed by the lack of single-qubit readout and the so far unknown relationship between qubit performance and chemical structure. Within ReadBITS, diradicals, i.e. organic molecules with two unpaired electron spins in their ground electronic state, will be integrated with carbon nanotubes (CNTs) working towards methods for single entity readout of the spin states, either electrically or optically. Recent progress in the synthesis of such diradicals leads to an uncharted market for MQBs, where spin-spin interactions can be controlled through chemical synthesis. While ensemble measurements are promising, single-entity readout might only be possible through integrating the MQBs with other systems, such as CNTs. Within this project, different readout strategies will be designed based on both spin-to-charge and spin-to-photon conversion for MQB-CNT hybrids. This project will provide new routes towards single MQB readout, boosting the implementation of diradicals in quantum applications.

Researcher(s)

• Promoter: Cambré Sofie
• Co-promoter: Van Doorslaer Sabine
• Co-promoter: Vroemans Robby
• Fellow: Medina Rivero Samara Lourdes

Research team(s)

• Theory and Spectroscopy of Molecules and Materials (TSM²)

Project type(s)

• Research Project