This article was originally published in Vol. 2 of the Journal of Photonics for Energy on 8 June 2012 with an incorrect citation identifier (CID) of 011012. The paper was removed and republished online with the correct CID of 021012 on 11 June 2012. This change was made in order for the CID to reflect the correct volume number. For more information on the use of CIDs in JPE, see http://spiedigitallibrary.org/jpe/citation_format.