341 citations · 2.7k across the 51 of their papers we have counts for
10 papers · 1 filter
Graph-theoretical approach to the eigenvalue spectrum of perturbed higher-order exceptional points
Daniel Grom, Julius Kullig, Malte Röntgen +1
Exceptional points are special degeneracy points in parameter space that can arise in (effective) non-Hermitian Hamiltonians describing open quantum and wave systems. At an n-th or…
Moving along an exceptional surface towards a higher-order exceptional point
Jan Wiersig
Open systems with non-Hermitian degeneracies called exceptional points show a significantly enhanced response to perturbations in terms of large energy splittings induced by a smal…
Petermann factors and phase rigidities near exceptional points
Jan Wiersig
The Petermann factor and the phase rigidity are convenient measures for various aspects of open quantum and wave systems, such as the sensitivity of energy eigenvalues to perturbat…
Revisiting the hierarchical construction of higher-order exceptional points
Jan Wiersig
Higher-order exceptional points in the spectrum of non-Hermitian Hamiltonians describing open quantum or wave systems have a variety of potential applications in particular in opti…
Response strengths of open systems at exceptional points
Jan Wiersig
Open quantum and wave systems exhibit exotic degeneracies at exceptional points in parameter space that have attracted considerable attention in various fields of physics, includin…
Robustness of exceptional-point-based sensors against parametric noise: The role of Hamiltonian and Liouvillian degeneracies
Jan Wiersig
Recent experiments have demonstrated the feasibility of exploiting spectral singularities in open quantum and wave systems, so-called exceptional points, for sensors with strongly…
Non-Hermitian scattering on a tight-binding lattice
Phillip C. Burke, Jan Wiersig, Masudul Haque
We analyze the scattering dynamics and spectrum of a quantum particle on a tight-binding lattice subject to a non-Hermitian (purely imaginary) local potential. The reflection, tran…
Nonorthogonality constraints in open quantum and wave systems
Jan Wiersig
It is known that the overlap of two energy eigenstates in a decaying quantum system is bounded from above by a function of the energy detuning and the individual decay rates. This…
Spontaneous -symmetry breaking and exceptional points in cavity quantum electrodynamics systems
Yu-Kun Lu, Pai Peng, Qi-Tao Cao +4
Spontaneous symmetry breaking has revolutionized the understanding in numerous fields of modern physics. Here, we theoretically demonstrate the spontaneous time-reversal symmetry b…
Pitfalls in the theory of carrier dynamics in semiconductor quantum dots: the single-particle basis vs. the many-particle configuration basis
T. Lettau, H. A. M. Leymann, J. Wiersig
We analyze quantum dot models used in current research for misconceptions that arise from the choice of basis states for the carriers. The examined models originate from semiconduc…