Antiscarring of Periodic Orbits

Although chaos plays an essential role in many natural phenomena, such as forecasting the weather, its quantum nature remains elusive. One of the most intriguing quantum chaotic phenomena is the scarring of a single-particle wavefunction showing an enhanced quantum probability density in the vicinity of a classically unstable periodic orbit. More recently, this conventional scaring has been accompanied by two new scarring phenomena, namely many-body and perturbation-induced scars. Here, we discuss a necessary consequence of quantum scarring, referred to as antiscarring: a depression of the probability density in other quantum states along the path of the scar-generating periodic orbit. Besides justifying the existence of antiscarring, we are elucidating the concept exemplarily for a disordered two-dimensional quantum well exhibiting strong perturbation-induced scars. Our results shed light upon understanding the fundamental dilemma posed by reconciling the quantum formalism with the classical concept of ergodicity, even in the presence of quantum-mechanical suppression of classical chaos, such as scars. In addition to providing an insight into the thermalization of a generic quantum system, this may pave a way towards employing scarring in future quantum devices.