Hi Joseph,

Are you trying to quench instantaneously from 3 to 6 at t=0? If so, your code should be modified to

'TAUS' : [30.0], 'POWS' : [0.0], 'GS' : ['Jz'], 'GIS' : [6.0], 'GFS' : [6.0], 'NUMSTEPS' : [1250], 'STEPSFORSTORE' : [10]

Note that you only need single-element arrays, as you only have one quench. As it stands you have two quenches. The first is for zero time, and leaves \Delta at 3. The second ramps \Delta from 6 to 6 linearly over a timescale of 30. The error may be due to propagating with zero time step for the first quench. Let me know if this is still not clear, or if this doesn't help.

-Michael

On Wed, Aug 21, 2013 at 6:05 AM, Joseph Prentice < Joseph.Prentice@physics.ox.ac.uk> wrote:

Hi all,

I'm having a bit of trouble with getting a quench using the XXZ model to run in TEBD. I'm running the job on a Linux cluster, quenching Delta instantaneously from 3 to 6, and the program stops earlier than it should. I turned on the Verbose option, and it seems as though the imaginary time propagation works fine, but the real time propagation stops prematurely, with no error message. Does anyone have any idea why this has happened? It seems very odd. I will attach my Python script in case there is something wrong with it, and the output I obtained.

Thanks very much,

Joseph Prentice