Quantum metrology is on the brink of a revolution, and Dr. Mažena Mackoit-Sinkeviciene is at the forefront of this transformative wave. AZoQuantum recently sat down with her to explore how cutting-edge research is bridging the gap between theoretical physics and real-world applications. In this captivating interview, Dr. Mackoit-Sinkeviciene delves into the driving forces behind her work, the technical hurdles her team is overcoming, and how recent advancements are expanding the horizons of quantum technologies. From the broader scientific landscape to the intricate details of current experiments, this conversation offers a comprehensive and engaging snapshot of the field’s current state and its future trajectory.
Congratulations on the 2025 Baltic Women in Science Fellowship! But here's where it gets controversial: In a field often dominated by experimental breakthroughs, your theoretical contributions have stood out. What specific milestone do you believe most convinced the jury of your impact in quantum technologies?
Thank you, this recognition is truly humbling. As a theoretical quantum physicist, my impact isn’t tied to a single experiment but to the development of frameworks that guide and enable experiments over time. I believe the jury was particularly impressed by the enduring impact and practical relevance of my work across two distinct yet complementary quantum platforms: solid-state quantum emitters and ultracold atomic systems. A standout milestone was my work on point defects in diamond and hexagonal boron nitride (hBN) as quantum emitters. Collaborating with others, I developed a microscopic theoretical model pinpointing the carbon dimer defect as the source of ultraviolet quantum emission in hBN. Though purely theoretical at first, this model was experimentally validated years later in 2025 by multiple international groups, including researchers at CNRS Université de Montpellier. This delayed confirmation not only validated the theory but also demonstrated its predictive power in guiding complex experimental efforts in quantum communication materials and their integration into photonic platforms.
Equally pivotal was my later work on nonclassical spin states in ultracold atomic gases, where we crafted analytically tractable and experimentally realistic models for spin squeezing—a technique crucial for quantum-enhanced metrology and sensing. I believe the jury appreciated this blend of theory, experimental relevance, and cross-platform thinking, as well as my broader engagement with the quantum community through policy work, education, and European quantum initiatives. Together, these elements showcase an impact that transcends individual results, contributing to the long-term growth of quantum technologies.
And this is the part most people miss: The interplay between solid-state quantum emitters and ultracold atomic systems has been a game-changer for my research. Transitioning between these platforms deepened my understanding of how coherence and noise limit quantum technologies. While solid-state systems often grapple with noise at the individual defect level, cold-atom systems offer a unique playground to study how engineered quantum correlations can mitigate these challenges collectively. This shift not only broadened my perspective but also reinforced the importance of analytically tractable models that remain experimentally grounded.
Currently, I’m pushing the boundaries of the standard quantum limit in precision measurements, particularly in frequency metrology for advanced timekeeping. This limit stems from quantum projection noise in uncorrelated atomic ensembles. To surpass it, we’re developing spin-squeezing protocols using engineered atom–light interactions in ultracold fermionic systems. A key innovation here is the use of position-dependent laser phases and spin–orbit coupling to generate effective one-axis and two-axis twisting dynamics without relying on strong intrinsic interactions. These strategies are compatible with existing cold-atom platforms and offer realistic pathways to enhance precision in optical clocks and quantum sensors.
But here's where it gets controversial: When atoms interact with structured light, as opposed to plane-wave illumination, entirely new physics emerges. Structured light, especially beams carrying orbital angular momentum and spatially varying polarization, opens novel light–matter coupling channels. Unlike plane waves, these fields imprint their spatial phase and polarization structure directly onto atomic coherence, manifesting as phase-dependent dark states, orbital angular momentum exchange, and polarization-controlled transparency in atomic media. These effects enable spatially resolved control of quantum states and pave the way for high-dimensional quantum information encoding, moving beyond the conventional two-level qubit paradigm. We probe these phenomena by analytically solving the Maxwell–Bloch equations for vector vortex beams interacting with multi-level atomic systems, providing quantitative predictions ripe for experimental testing.
A recent experiment exemplifying our approach involves generating spin squeezing in an atomic Fermi–Hubbard system using laser-induced coupling. The signal we aim to extract—a reduction of quantum noise below the shot-noise limit—is incredibly weak, appearing in spin fluctuations rather than mean populations. Our strategy is to engineer the system so this weak signal is both protected and structured. By operating in the Mott-insulating regime and applying position-dependent laser coupling, we generate controlled one- and two-axis squeezing dynamics. The squeezing is then extracted through Ramsey-type measurements, scanning spin quadratures to identify the minimum variance relative to a calibrated shot-noise reference. What sets our approach apart is our avoidance of amplification; instead, we design dynamics so that genuine many-body correlations have a predictable and robust signature, distinguishing them reliably from technical noise. This is critical because surpassing the shot-noise limit enables higher measurement precision without increasing atom number—a necessity for next-generation atomic clocks and quantum sensors.
The most promising applications for our techniques lie in quantum-enhanced timekeeping and quantum interferometry. Spin-squeezed states directly improve phase and frequency sensitivity, vital for optical atomic clocks and interferometric measurements. Enhanced clock stability also has downstream benefits for navigation and GPS-like systems, where precise time synchronization underpins positioning accuracy. Beyond clocks, these methods are highly relevant for precision interferometry and tests of fundamental physics. In a recent review, I highlighted progress on large-scale atom interferometer prototypes and discussed future applications of squeezed-state interferometry for detecting ultralight dark matter and gravitational waves. Reducing quantum noise through squeezing is becoming a cornerstone of next-generation interferometric sensors.
However, here’s the challenge most people overlook: Moving from lab demos to deployable devices requires closing significant technical gaps, including extending coherence times, scalable and robust preparation of squeezed states, and integration into compact, stable platforms. Our work addresses these challenges by proposing experimentally feasible schemes compatible with existing cold-atom, clock, and interferometry architectures, helping bridge the gap between laboratory demonstrations and real-world quantum sensors.
International and cross-disciplinary collaborations have been pivotal to my progress. Partnerships with experimental groups in Europe, the United States, and Australia ensured my theoretical work remained grounded in experimental realities, often directly informing experimental design and interpretation. Interdisciplinary interactions spanning condensed matter physics, quantum optics, and atomic physics unlocked capabilities that would be unattainable within a single subfield.
I plan to leverage the Baltic Women in Science Fellowship to accelerate my research agenda while amplifying the international visibility of Baltic quantum science. Scientifically, the award will support deeper integration of my work on quantum metrology and quantum emitters into European quantum research programs, fostering new collaborations and joint projects with leading groups. Equally important, I aim to use this award for community building, connecting early-career researchers from the Baltic region to European quantum initiatives. My experiences contributing to Lithuania’s National Quantum Agenda, co-founding Quantum Lithuania, and representing the country in the Quantum Flagship Community Network have reshaped my view of a scientist’s role. Long-term impact demands not just excellent research but also education, coordination, and international integration. Moving forward, I’ll use this award to strengthen regional leadership in quantum science, ensuring the Baltic community is a visible and active contributor to the global quantum ecosystem.
Thought-provoking question for our readers: As quantum technologies advance, how can we ensure that smaller regions like the Baltics not only participate but also lead in this global revolution? Share your thoughts in the comments below!
About the Speaker: Dr. Mažena Mackoit-Sinkeviciene is a researcher at the Institute of Theoretical Physics and Astronomy, Faculty of Physics, Vilnius University, specializing in quantum optics and quantum technologies. Her work focuses on quantum emission from point defects in solid-state platforms and nonclassical spin states in ultracold atomic gases, with applications in quantum computing, optical atomic clocks, and quantum sensors. Her findings have been applied by international experimental collaborators, earning her prestigious awards, including the 2025 Baltic Women in Science Fellowship. Dr. Mackoit-Sinkeviciene is also a co-author of Lithuania’s National Quantum Guidelines and serves as Vice President of the Lithuanian Physical Society.
Disclaimer: The views expressed here are those of the interviewee and do not necessarily represent the views of AZoM.com Limited (T/A) AZoNetwork, the owner and operator of this website. This disclaimer forms part of the Terms and Conditions of use of this website.
