Quantum Materials and the Next Generation of Quantum Technologies

The 2025 Nobel Prize in Physics honored John Clarke, Michel H. Devoret and John M. Martinis for demonstrating macroscopic quantum tunnelling and discrete energy levels in superconducting electrical circuits. Their experiments turned Josephson-junction circuits into “artificial atoms”, large enough to pattern on a chip yet fully governed by quantum mechanics. These devices are the direct ancestors of today’s superconducting qubits used in many quantum computers, a hallmark of the second generation of quantum devices. A key theoretical pillar of this achievement is the Caldeira–Leggett model of quantum dissipation, developed by Brazilian physicist Amir O. Caldeira and collaborators, which explains how an environment suppresses or modifies tunnelling in macroscopic systems. 

While current superconducting qubits rely mostly on aluminum junctions operated near absolute zero, the future of quantum technologies increasingly depends on more advanced materials – the quantum materials: unconventional superconductors, topological materials, strongly correlated electron systems, magnetic oxides, and low-dimensional compounds. The realization that macroscopic circuits can operate coherently opened the door to a new generation of quantum materials — systems engineered to host, sustain, manipulate, and protect quantum states in macroscale. These materials promise longer coherence times, robustness against noise, exotic quasiparticles such as Majorana modes, and hybrid platforms that couple spins, photons, and superconducting degrees of freedom. Unconventional superconductors, for example, offer pairing mechanisms beyond the traditional s-wave scenario, potentially enabling ultimate quantum sensors and fully non-dissipative electronic circuits. Topological insulators and semimetals host edge states immune to disorder, appealing for fault-tolerant quantum logic. Strongly correlated materials — ranging from heavy-fermion compounds to moiré systems — host a variety of emergent quantum phases that can be harnessed for quantum simulation, sensing, etc.

Although Brazil’s efforts in the development of quantum materials and technologies still lag behind those of leading countries, significant progress has been achieved in recent years. This includes projected investments of up to R$5 billion over the next eight years dedicated to research and development in quantum computing. More recently, two new National Institutes of Science and Technology (INCTs) have been approved with a focus on research and development of quantum materials and quantum devices in Brazil. Among these initiatives, the INCT – Advanced Quantum Materials (MQA) has been established with the goal of investigating and developing new quantum materials that may enable the emergence of a new generation of quantum devices, already incorporating within its program the development of devices based on these materials. The central objective of INCT-MQA is to connect the Brazilian research community working on strongly correlated materials, superconducting materials, and topological materials, fostering collaboration aimed at advancing the fundamental understanding and technological exploitation of quantum materials.