Controlling Quantum Interference for Molecular Electronics

Thanks to their sub-10 nanometre size, molecules offer a fantastic platform for exploiting quantum effects at room temperature. Recently, it was shown that molecular wires can mediate long-range, phase-coherent tunnelling with remarkably low attenuation beyond a few nanometres, even at room temperature [1]. This opens up the possibility of using quantum interference (QI) to control the transport of electrons, spins and phonons through molecular junctions consisting of a single or a few molecules between electrodes.<br/><br/>In this talk I will present evidence for room-temperature QI in molecular junctions and discuss the agreement and disagreement between experiments and predictions based on phase-coherent quantum transport theory [2]. Then, I will discuss strategies to control QI in molecular junctions [3] including chemical and structural modifications of molecules, and the application of electric field or light. I will then discuss how these strategies can be used to improve the efficiency of thermoelectric materials for energy harvesting and cooling, to improve spin filtering through molecules for quantum information applications, and to selectively sense biological species.<br/><br/><b>References</b><br/>[1] Chem. Mater. 25 (21), 4340, <b>2013</b>; Nano Lett. 22 (18), 7682, <b>2022</b>.<br/>[2] <i>PNAS</i>, 112(9), 2658, <b>2015</b>; <i>Nature Materials</i>, 18(4), 364, <b>2019</b>; <i>JACS</i>, 137(13), 4469, <b>2015</b>; <i>Nano Lett</i>., 18(7), 4482, <b>2018</b>; <i>JACS</i>, 140(40), 12877, <b>2018</b>; <i>Nanotechnology</i>, 29, 373001, <b>2018</b>.<br/>[3] <i>Nano Lett</i>., 22, 3, 948, <b>2022</b>; <i>JPCL</i>, 13(39), 9156, <b>2022</b>; <i>Nanoscale Adv</i>., 2(3), 1031, <b>2020</b>; <i>Nature Comm.</i> 11, 5905, <b>2020</b>; <i>Angewandte Chem</i>, 61, e2021169, <b>2022</b>; <i>ACS Nano</i>, 14(5), 5754, <b>2020</b>; <i>Nanomaterials</i> 10 (8), 1544, <b>2020</b>; <i>JACS</i>, 143(25), 9385, <b>2021</b>; <i>PCCP</i>, 21, 2378, <b>2019</b>; <i>Nano Lett</i>., 20(11), 7980, <b>2020</b>.