Al-Khalili obtained his PhD (1986–1989) in nuclear reaction theory from the University of Surrey, during which he developed a reaction model to study the importance of the tensor force in polarized deuteron scattering at high energies. His work helped tie down certain aspects of the role of the strong force in nuclear scattering. He showed that during its interaction with a target nucleus, the deuteron can be excited to an intermediate spin singlet state, which is needed to reproduce the vector and tensor analysing powers. During his PhD, Al-Khalili also published papers on the effects of Pauli blocking on deuteron scattering and on the Schrodinger reduction of the Dirac equation.
Following his PhD, he was awarded a two-year SERC Fellowship (1989-1991) to work at UCL where he published his first single author paper and worked with Colin Wilkin on modelling h-meson production in nuclear reactions. During this time, he also extended his PhD work by developing the first parameter-free few-body computer code with full spin-dependence.
By the early 90s, and having returned to the Surrey nuclear theory group, he became interested in relativistic wave equations, such as the Kemmer-Duffin-Petiau equation, and developed a new optical model formalism for both alpha and deuteron elastic scattering. It was around this time that he became interested in the new field of halo nuclei. These strange entities owe their existence to Heisenberg’s Uncertainty Principle and canbest be modelled as one or two valence neutrons (the halo) weakly-bound to a nuclear ‘core’. Al-Khalili extended the model he had previously applied to deuteron scattering to study 11Li, the most exotic of the halo family. Such 3-body nuclei are unusual in that any two of the three subsystems (core-n or n-n) are unbound. They have thus been dubbed ‘Borromean’ after the three interlocked Borromean rings in knot theory. Al-Khalili was the first to successfully implement a ‘four-body’ scattering model (3-body projectile interacting with a target nucleus), which took fully into account the few-body correlations (the Borromean characteristics) in the halo.
In 1994, Al-Khalili was awarded a five-year EPSRC Advanced Research Fellowship and began the most research-intensive period of his career, publishing at the rate of a paper every few months. His two most high-cited papers were written at this time. He followed these up with several other important papers. After several months working at the Niels Bohr Institute in Copenhagen he embarked on a lecture tour of Japan talking about his results.
Towards the end of his Fellowship Al-Khalili developed a new quantum scattering model that extended his few-body Glauber approach to include non-eikonal corrections. In 2000, having been promoted to senior lecturer, he was appointed to a one-year Adjunct Professorship at Michigan State University where he developed areaction model for single nucleon knockout and stripping reactions involving neutron-rich isotopes of Beryllium and Carbon.
The summers of 2002-2004 were spent at TRIUMF Lab in Canada where Professor Al-Khalili worked on radioactive decay studies of nuclei, particularly proton emission along the proton dripline. In 2004, he was the only theorist among twenty experimental physicists on a paper in which he provided the theoretical interpretation of data that confirmed for the first time the existence of neutron halos in excited nuclear states. He followed this up with a paper on 10Be in 2006.
Al-Khalili had also become interested in the possibility of probing the structure of the halo using charged pion photo-production reactions. While pion production on a nucleon had been extensively studied for many years, the production processes in composite nuclei remain unclear. This interest led him back to hadron physics, a field that sits between nuclear and particle physics. He worked on a quark model for meson photo-production in which the quark degrees of freedom are explicitly introduced through an effective chiral Lagrangian for the quark meson coupling. The papers on the structure and properties of the hypothetical pentaquark using this model have been highly cited. Al-Khalili continued to retain his interest in halo nuclei and published a review paper on the field in 2003 and a monograph ‘Halo Nuclei’ in 2017.
His work on quantum biology, which began as a side interest in the late 90s, is now a major research focus for Al-Khalili. He had previously collaborated with physicist Paul Davies (Arizona State) and microbiologist Johnjoe McFadden (Surrey) on developing a proton tunnelling model to model a certain type of genetic mutation and published an early speculative paper in 1999. Most recently, Al-Khalili has been calculating the effects of proton tunnelling in mutations in DNA by solving the Markovian Master equation (for open quantum systems) to simulate H-bond base transitions. They have shown a correspondence between two theoretical models of environment induced de-phasing that sheds light on the quantum measurement problem and have used density functional theory to map the potential energy surface for hydrogen bonds between nucleotide base pairs to calculate the proton tunneling rate. Together with McFadden, Al-Khalili wrote the first general interest book on the subject, Life on the Edge: the coming of age of quantum biology, which was shortlisted for the Royal Society Winton Book Prize for 2015 and has been translated into 16 languages. He is currently setting up a cross-disciplinary quantum biology research group at Surrey. In 2015, he gave a TED talk on his work in quantum biology, which has been watched1.5 million times.
Another side to Al-Khalili’s academic research has been his work in the history of science. In 2015, he published an analysis of the work of Michael Faraday for the 350thanniversary of the Royal Society’s Philosophical Transactions as well as a paper on medieval optics. He has also recently submitted a paper on the history of quantum biology. Al-Khalili has recently written a monograph on halo nuclei for the Institute of Physics’ Concise Physics series of graduate textbooks.