Hi Michael, sorry I've been slow on the reply, I didn't see this response. Thank you very much, this seems to have worked! My code had worked for lower Chi values, but when I increased the Chi value beyond a certain point, I experienced the problem I mentioned. Thank you for solving it!

Joseph

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Message: 2 Date: Wed, 21 Aug 2013 12:05:05 +0000 From: Joseph Prentice Joseph.Prentice@physics.ox.ac.uk To: "comp-phys-alps-users@lists.phys.ethz.ch" comp-phys-alps-users@lists.phys.ethz.ch Subject: [ALPS-users] Time propagation in TEBD stops prematurely Message-ID: 747861816F6A5C47BE50FCA07F5B2B4A0E25BB@EXCHNG16.physics.ox.ac.uk Content-Type: text/plain; charset="us-ascii"

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