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                                                                   EXHIBIT 10.24

                          NON-RECOURSE PROMISSORY NOTE

$6,528,248                                                         April 1, 2003

     FOR VALUE RECEIVED, Dr. Valentin P. Gapontsev ("Maker") promises to pay to
IPG Photonics Corporation, a Delaware corporation (the "Company"), or order, the
principal sum of SIX MILLION FIVE HUNDRED AND TWENTY EIGHT THOUSAND TWO HUNDRED
AND FORTY EIGHT DOLLARS ($6,528,248), together with interest (compounded
annually) on the unpaid principal hereof from the date hereof at an annual rate
of 1.46%.

     Interest and principal shall be due and payable on December 31, 2004 or
nine months following an initial public offering by the Company, whichever is
earlier. Payments of principal and interest shall be made in lawful money of the
United States of America. The Maker may at any time prepay all or any portion of
the principal or interest owing hereunder without penalty.

     This Note is secured pursuant to the terms of a Pledge Agreement between
the Maker and the Company, dated as of March 5, 2001, as amended from time to
time (the "Pledge Agreement"). Notwithstanding anything contained herein to the
contrary, this Note (including all interest and principal) is a non-recourse
obligation of Maker and such Note shall be enforced against Maker only to the
extent of Maker's interest in the collateral pledged under the Pledge Agreement
in the event of default hereunder, provided that IP Fibre Devices (UK) Ltd.
("IPFD") shall not have defaulted in its obligations under the Loan and Security
Agreement, dated as of August 23, 2002, between the Company and IPFD, as amended
from time to time, and such default shall have continued for a period of five
business days after receipt of written notice of the default.

     Maker shall immediately repay to the holder of this Note any tax refunds
received by Maker or his successors or assigns from the German Government in
respect of income taxes paid by Maker for the reorganization of the corporate
structure and holdings of the Company and its affiliates.

     In the event the Maker shall cease to be an employee of the Company for the
following reasons:

          A. The Company reasonably determines in its discretion that Maker has
been materially negligent in the performance of, or materially fails to perform,
Maker's duties, or has failed to comply with the reasonable and material
directions of the Company, provided that the Company has given Maker written
notice of the deficiencies in performance or failure to comply and Maker has
failed within thirty (30) days after service of such notice to cure such
deficiencies to the Company's satisfaction;

          B. The determination by the Company in the exercise of its reasonable
judgment that Maker has committed an act or acts constituting fraud with respect
to the Company, or the Maker has been convicted of, or

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admits to, or enters a plea of nolo contendere to a felony or any crime
involving moral turpitude; or

          C. In the event of the Maker's termination of employment with the
Company for any reason, other than for the following:

               i.   The assignment to Maker of any duties materially
                    inconsistent (except in the nature of a promotion) with
                    Maker's position in the Company or a substantial adverse
                    alteration in the nature of Maker's position or
                    responsibilities or in the conditions of employment;

               ii.  A reduction by the Company in Maker's then-current salary or
                    a material reduction in benefits; or

               iii. A termination of employment with the Company without cause;
                    or

          D. The declaration of or filing for bankruptcy or insolvency by the
Maker,

then, this Note shall, at the option of the Company, be accelerated, and the
whole unpaid balance on this Note of principal and accrued interest shall be
immediately due and payable. After default in the required payment of principal
or interest, or the acceleration of this Note, then interest shall thereafter
accrue at rate of the stated interest above plus 2% per annum.

     Should any action be instituted for the collection of this Note, the
reasonable costs and attorneys' fees therein of the holder shall be paid by the
Maker, subject to the non-recourse limitations of this Note.

     This Note shall be governed by the laws of the Commonwealth of
Massachusetts, without giving effect to its choice of law principles thereof.

     This Note supersedes and replaces in its entirety the Promissory Note,
dated March 5, 2001, having a maturity date of March 5, 2002, and the Amended
and Restated Promissory Note, effective March 5, 2001 and having a maturity date
of December 31, 2004.


                                        /s/ Valentin P. Gapontsev
                                        ---------------------------------------
                                        Dr. Valentin P. Gapontsev

                                        Executed and Delivered

                                        As of this 1st day of April, 2003
