Tagged Questions
-1
votes
2answers
145 views
Quantum tunneling is faster than light travel?
Quantum tunneling is faster than light travel ?
My reasoning is that the particle cannot be detected inside the tunnel so if it travels from A to B it must be instantly going from A to B , hence ...
1
vote
2answers
179 views
Tunneling v. Hopping
Can someone explain the difference between hopping and tunneling? The context I'm considering is conduction in semiconductors, specifically between impurity states within the bandgap. It's always ...
1
vote
1answer
163 views
How is quantum tunneling possible?
How is quantum tunneling possible?
According to quantum mechanics, each particle is represented by a probability density function. This function must be continuous, and therefore when we look at a ...
4
votes
1answer
131 views
Hawking Radiation from the WKB Approximation
Reading this paper which is itself an exposition of Parikh and Wilczek's paper, I get to a point where I fail to be able to follow the calculation. Now this is undoubtably because my calculational ...
5
votes
2answers
129 views
Is there a time delay during tunnelling?
A particle hitting a square potential barrier can tunnel through it to get to the other side and carry on. Is there a time delay in this process?
1
vote
2answers
171 views
Where does the “borrowed energy” come from in Alpha decay?
I was also thinking about the uncertainty principle in regards with energy & time. The question of something like:
Alpha tunneling out of the nucleus is where this can be invoked, but having an ...
2
votes
0answers
79 views
What can tunnel through a graphene sheet?
In popularizations, people tunnel through walls or doors. But what can really tunnel through a graphene sheet without tearing it?
According to Wikipedia, a single layer of graphene absorbs 2.3 % ...
2
votes
1answer
806 views
How to solve Schrodinger Equation - Tunnelling
I have to solve analitically the Schrodinger equation in one-dimension with a barrier of potential (tunnel effect):
$$ih \frac{d}{dt} U(x,t) = \left[ \left(-h^2 \frac{d^2}{dx^2} \right) + q V(x) ...
5
votes
1answer
221 views
Chance of “macro tunneling”?
We know that subatomic particles can and do tunnel through barriers, so it is theoretically "possible" somewhat that a grain of sand could tunnel through a paper, but Id like to get some perspective ...
10
votes
7answers
1k views
Can a particle be *physically* observed inside a quantum barrier?
I understand that a particle approaching a finite potential barrier with $E < V_0$, there still is a probability of finding the particle on the other side of the barrier due to quantum tunneling.
...
5
votes
2answers
704 views
Tunneling of alpha particles
Consider this explanation of the alpha decay: It says
The Coulomb barrier faced by an alpha
particle with this energy is about 26
MeV, so by classical physics it cannot
escape at all. ...
4
votes
4answers
408 views
Where is the particle during a tunneling event?
If, say, a particle with energy $E<V_0$, approaches a finite potential barrier with height $V_0$, and happens to tunnel through, where would the particle be during the time period when it is to the ...
5
votes
3answers
610 views
Why is tunneling not a classical idea?
There is no tunneling in the case of infinite potential barrier, but there is when we have a finite well. In the classical analog, in the first case we have a particle bouncing between to infinitely ...
