What is quantum physics? And what exactly does a quantum physicist do every day? We speak to Dr Sridevi Kuriyattil to find out more.
Quantum physics is the branch of physics that describes how matter and energy behave at the smallest scales – atoms, electrons, photons, and beyond. Unlike classical physics, where you can predict an object’s path by knowing its position and velocity, quantum systems follow very different rules.
Particles in the quantum world can exist in multiple states at once which is known as superposition. They can become entangled, meaning their properties become deeply linked; measuring one gives you information about the other, even if they’re far apart – Albert Einstein famously called this ‘spooky action at a distance’. These counterintuitive ideas aren’t just theoretical; they have been confirmed in countless experiments and form the foundation of modern technologies such as lasers, semiconductors, and medical imaging techniques like MRI.
The work of a quantum physicist
I work as a computational and theoretical physicist in the field of quantum many-body physics and quantum information theory. My daily work is a blend of maths, coding, collaboration, and the occasional blackboard brainstorming session. Broadly speaking, my work includes simulating quantum systems especially those involving many particles interacting with each other; I write and run code to study how quantum systems evolve and generate entanglement. My personal favourite languages are Python and Julia but I imagine you would get different responses from different people!
My work as a theorist means I develop theoretical insights to guide my experimentalist colleagues. My work helps them avoid costly trial-and-error as I am able to identify optimal parameters before they start performing any experiments.
A big part of being a scientist in any discipline is about attending and presenting at conferences both in the UK and abroad. Conferences are where we share results through talks and posters and often, the connections we make might result in initiating collaborative projects together.
I also make time to participate in outreach programs as I particularly enjoy finding creative ways to explain abstract quantum ideas to broader audiences. For example, using interactive games like quantum tic tac toe, quantum chess etc (these are already available online and is not my novel games) to teach concepts like entanglement and superposition.
A typical day
All of this means that, for me, a typical day might look something like this… I tend to start at the blackboard, sketching out equations or models, to understand the physics before writing any code. Once I have a direction of travel, I will move on to my laptop and start writing up simulations for quantum systems.
I then get to analyse the results to see if anything emerges or if anything is useful and I often have the opportunity to discuss my findings with colleagues. For me, collaboration is key to being the best scientist I can be; I regularly connect with colleagues, collaborators or experimental partners and it is always interesting to have another person’s perspective on a scenario.
Many-body quantum dynamics
The actual ‘physics’ that I work on is quantum many-body dynamics in sparse coupling graphs. These are systems where the underlying graph of interactions is not densely connected and there are two main reasons to study such graphs. First, from an experimental perspective, it is feasible to simulate their dynamics using platforms such as neutral atom arrays, atoms in optical cavities, and trapped ions. Second, from a theoretical standpoint, sparse graphs exhibit many intriguing properties – making them both rich in physics and genuinely enjoyable to work with.
In recent work, we demonstrated that these graphs can generate entangled states at a time that scales logarithmically with system size N. Thus, these graphs maybe useful in creating states within the coherence time that is, before decoherence or noise significantly alters the system. Such useful entanglement is a key resource in quantum technologies, particularly in quantum-enhanced metrology, where the canonical task is phase estimation. Our results showed that sparse graphs can successfully support this process as well.
I am all buckled up to see what rich physics these sparse graphs have to offer us, particularly their potential for quantum information processing, and non-ergodic dynamics. During my PhD, I had the valuable opportunity to collaborate closely with the experimental team at the University of Strathclyde, working with neutral atom arrays. This experience has deepened my appreciation for hardware-informed theory. Now I am keen to engage with the ion trap platform and explore its capabilities for realising tailored interactions using sparse coupling graphs.
An inspirational teacher
I think my real interest in physics began during my final years of school, thanks to an inspiring teacher who went beyond the curriculum to take extra classes, answer all my questions, and encourage me to participate in physics olympiads. After completing school, it meant I was keen to then pursue STEM subjects. Following a series of competitive examinations, I was admitted to the Indian Institute of Science Education and Research (IISER) Bhopal where I had the chance to explore a wide range of subjects: physics, biology, chemistry, economics, and the humanities. While every subject had its own appeal, I found myself particularly drawn to mathematics and physics; I enjoyed problem-solving, and physics was especially exciting because the problems helped uncover more about the world around us.
After completing my master’s degree, I moved to the University of Strathclyde for a PhD under the supervision of Professor Andrew Daley who subsequently moved to Oxford in 2024. Not only have I been able to pursue my PhD but now I am fortunate to be able to continue as a postdoctoral research assistant. It has been an incredible journey so far supported by a lot of wonderful mentors and I am still driven by a fascination to understand the world around us.
To anybody wanting to pursue a career as a quantum physicist, my number one piece of advice would be to stay curious which means keep asking questions – even the ones that seem simple. In quantum physics, no question is too basic, and the most interesting discoveries often begin with curiosity about the fundamentals. It is important to build a strong foundation in maths and physics, but also be open to learning programming and working with experimental tools if needed. Most importantly though, don’t be afraid of making mistakes – they are part of the learning process. And seek out others; find peers, mentors, or teachers who encourage you to think deeply and creatively as science thrives in collaborative spaces.
100 years of quantum
This year celebrates 100 years of quantum. From Einstein’s famous remark about entanglement to modern experiments that engineer and harness entanglement in atomic, molecular, and optical systems, the field has seen astonishing progress. These are truly exciting times: analogue quantum simulators are helping us understand complex phenomena like quantum many-body systems, and there’s remarkable progress in building fault-tolerant gates for digital quantum computers. Over time, these advancements will undoubtedly deepen our understanding of how entanglement builds up and help us observe exotic physics.