Maximum number of particles for MCTDHB

[asakhel]

Dear all,

  I just wanted to ask if MCTDHB can handle calculations with N=2000 particles
in three dimensions, like in a quasi-1D cigar trap. I know for example some
methods cannot handle more than 200 particles, etc.

Thank you
--Asaad Sakhel

[mctdhb]

Hi Asaad Sakhel!

The accuracy of MCTDH-B is dependent on the physical situation that is considered.
The size of the configuration space is N+M-1 choose N ; so for N=2000 particles you can work at most with M=3 orbitals.

If these 2003001 configurations would be a sufficiently large configuration space for the system you have in mind, then yes.

For instance, I think you could get a very accurate representation for harmonically, double-well, and triple-well trapped particles.
There exist many examples where MCTDH-B has been applied for N>200, for instance:

https://www.pnas.org/content/109/34/13521
https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.106.240401
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.100.130401

Best,
Axel