Famous for the wave-like behavior of matter exhibiting interference and superposition. quantum double slit experiment, demonstrated for the first time with molecules used as slits. Richard Feynman He once said that the double-slit experiment uncovered the puzzles of quantum mechanics and confronted us "with the paradoxes, mysteries, and quirks of nature." As a groundbreaking scientist in the conceptual part of the physics world, Feynman's place is indisputable in the Quantum World. In a sense, Deuterium Molecules were now part of the Classical Quantum Slit Experiment.
So in this experiment, molecules are used as slits instead of using a mechanical part that we know.
Richard Zare, Nandini Mukherjee and Stanford University researchers have shown that scattering that occurs when helium atoms in quantum superposition collide with deuterium molecules can interact and take two different paths.
The researchers observed that interference occurred by looking at the effects on the scattered deuterium molecules, which lost their rotational energy in the collision of the experiment.
Let's give a brief information about the slit experiment.
The slit experiment, which is one of the first topics of the introductory quantum mechanics course, is one of the most famous experiments in the Quantum World. This experiment proved that light can be both a wave and a particle.
Zare and his colleagues created an ultra-cold molecular beam of a mixture of deuterium and helium by experimenting with collisions at an effective temperature of 1K (–272°C).
Using two sets of polarized helium lasers, they separated deuterium molecules from one another based on a specific energy state and reference. In a sense, the laser acted as two "slits" that scatter the deuterium atoms.
Most importantly, the researchers could also prepare the deuterium molecules in a harmonious superposition of both orientations.
That is, the wave functions of the two overlapping states would remain in sync with each other.
When helium atoms scatter from the overlapping molecules, the atoms sense both orientations simultaneously.
In the classical double-slit experiment, each of the quantum particles passes through both slits in a superposition of orbitals. In this case, on the contrary, it would be as if there was only one slit in which the positions overlapped.
Physical chemist David Clary of the University of Oxford in England adds that the study allowed us to understand the different-valued rotational states of molecules of molecular scattering.
“An experiment that can measure such transitions in all initial and final quantum states has been a goal for a long time,” he says.
“Progress has been made in this direction,” the Stanford team adds, using quantum interference to reveal different spin states.
Quantum interference effects have been seen before in molecular scattering.
In a previous experiment, interference was observed for photoelectrons emitted from an oxygen molecule. Each electron could interact with any of the two atomic nuclei.
But what makes this experiment different is "we have full control of the rifts," it says. They are not in a fixed relationship as in a diatomic molecule.
However, he says they are formed by the overlapping of the molecular so that they can be adjusted at will. For example, he adds, the adjustments made are like changing the slit width.
Clary hopes to achieve quantum control of an experiment in which all the initial and final quantum states of the scattering molecules are selected.
Mukherjee says the approach would also work for bimolecular gas-phase chemical reactions. In this case, he says, "you can control the product of reactive chemical collisions" with quantum precision.
The researchers believe their results also explore fundamental aspects of quantum behavior.
“We describe the preparation of a new kind of substance: a known and controllable phase with overlapping states. In other words, it's a molecule that's prepared for its phased states," he says.
He says his methods can be used to study incongruity, where quantum phenomena turn into classical results through interactions with the environment.